WO1993021260A2

WO1993021260A2 - Lignin in wood composites

Info

Publication number: WO1993021260A2
Application number: PCT/US1993/003372
Authority: WO
Inventors: Jacob Ash; Chih Fae Wu; Albert W. Creamer; Jairo H. Lora; Joseph D. Rawus; George Shelton; William C. Senyo
Original assignee: Alcell Technologies Inc.
Priority date: 1992-04-09
Filing date: 1993-04-09
Publication date: 1993-10-28
Also published as: FI944647A; EP0635037A4; WO1993021260A3; FI944647A0; CA2133740A1; AU4596193A; EP0635037A1

Abstract

Novel adhesives for wood composites are described. The adhesives comprise a novel combination of an organosolv lignin and a phenol-formaldehyde resin in a weight ratio of from about 0.5:99.5 to about 70:30 based on phenolic solids in said phenol-formaldehyde resin. The adhesives further comprise a modifier which improves the performance of the adhesive. Adhesives comprising an organosolv lignin and a liquid phenol-formaldehyde resin are also described. The organosolv lignin solution is comprised in either an alkaline solution or in a dispersion. Adhesives wherein the organosolv lignin is phenolated or methylolated prior to incorporation with the phenol-formaldehyde resin are also described. Wood composites such as plywood, waferboard, oriented strandboard, particleboard, wallboard and molded products were manufactured using the adhesives of the invention. Results of board testing demonstrate that the wood composites of the invention are competitive with wood composites manufactured using commercial adhesives.

Description

LIGNIN IN WOOD COMPOSITES

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation-in-part of International Patent Application Serial No. PCT/US92/02963 filed April 9, 1992 entitled "IMPROVED LIGNIN-BASED WOOD ADHESIVES" which is a continuation-in-part of Application Serial No. 07/682,565, filed April 9, 1991 entitled "LIGNIN-BASED WOOD ADHESIVES".

BACKGROUND OF THE INVENTION

^' The pulp and paper industry produces tremendous quantities of kraft and sulfite lignins which, for the most part, are either burnt as fuel in high pressure

- boilers or discharged as waste with a consequent negative environmental impact. Although wood chemists have for many years addressed the problem of locating useful non- fuel applications for these lignins, currently less than 2% of all lignins available from spent pulping liquors are recovered and marketed for non-fuel uses. Accordingly, there exists a long-standing and ongoing need to implement new, non-fuel ways of effectively using lignin and other biomass by-products.

Typical phenol formaldehyde adhesives which are used in the manufacture of structural wood products such as plywood, waferboard, oriented strandboard and fiberboard contain many constituents in addition to the resin. In the case of plywood, while the resiri is the main constituent, various extenders, accelerators, fillers, viscosity control agents and other additives are generally added to the resin to control the properties of the formulation. While some of the added constituents are less costly than the resin itself, phenol-formaldehyde resins are not usually suitable for the formulation of low-value products. Furthermore , since the availability of phenol which is one of the main constituents of phenol- formaldehyde resins , is likely to become a problem as supplies of petroleum feed stocks decline in the future and as phenol's price rises steadily, there is a need to develop substitutes for phenol such as lignin.

Much work has been reported on the use of lignins from conventional processes as a component in the formulation of phenol-formaldehyde adhesives. Concentrated waste sulfite liquor has long been known to exhibit certain adhesive properties, and a common approach has been to substitute the spent sulfite liquor for a portion of the phenol in phenol-formaldehyde resins. The substitution is accomplished by pre-reacting the lignin with phenol prior to condensing it with the aldehyde. This approach has generally not been successful because of the poor reactivity of the lignins with phenol- formaldehyde.

Another major disadvantage of the use of spent sulfite liquor in adhesive formulations is the high water solubility of the adhesive after curing which makes such formulations unsuitable for exterior applications.

The use of spent sulfite liquors in adhesive formulations is further limited by their high polydispersity. In order to obtain uniform lignin fractions, ultrafiltration was attempted and specialty products are available for use in wood lamination. Attempts have been made to use kraft lignins in phenol-formaldehyde adhesive formulations. Since kraft lignins are relatively unreactive and sinter when heated, they are unsuitable for dry resin applications. Furthermore, when compounded with liquid phenol- formaldehyde resins, kraft lignins yield an over-viscous mixture. To enhance the reactivity of kraft lignins and improve on their potential for cross-linking, methylol groups have been added by reacting kraft lignins with formaldehyde.

Different formulations of phenolic adhesives containing lignins from conventional processes have been proposed. In U.S. Patent No. 3,956,207 to Blackmore et al., a ready-to-use phenolic adhesive for the manufacture of plywood containing heat treated spent sulfite liquor solids, is described. The phenol-formaldehyde resin is intermixed under alkaline conditions with spent sulfite liquor solids which are heat treated in a dry state until 20% to 50% of the dry heated solids are insoluble in an aqueous 0.5 molar sodium carbonate solution.

In ϋ.S Patent No. 3,957,703 to Ludwig et al. a phenolic-aldehyde _plywood adhesive was formulated with a water-insoluble, acid-polymerized . lignosulfonate. The lignosulfonate is polymerized from spent sulfite liquor to the extent that it will increase its dry bulk volume less than seven times upon exposure to water.

In ϋ.S. Patent No. 4,105,606 to Forss et al., an adhesive for the manufacture of plywood, fiber board, and similar products is described. The adhesive is a combina- tion of phenol-formaldehyde resin, and a lignin derivative such as lignosulfonates or alkali lignins. A minimum of 65% by weight^"of the lignosulfonates and a minimum of 40% by weight of the alkali lignins have relative molecular weights in excess of glucagon.

In U.S. Patent No. 4,127,544 to Allan, a phenol- formaldehyde resin adhesive is formulated in which a portion of the phenol ingredient is replaced with ammonium lignosulfonate.

As an alternative to spent sulfite liquors and lignosulfonates, organosolv lignin such as ALCELL^® lignin recovered by the process described in U.S. Patent No.

4,746,596 to Lora et al. can effectively compete with lignins produced from conventional processes in many applications. ALCELL^® lignin can be used in applications such as the formulation of phenol-formaldehyde lignin- based adhesives. In the recent work of Lora et al. , described in "Characteristics and Potential Applications of Lignin Produced by an Organosolv Pulping Process," ACS

Symposium Series No. 397, page 318, (1988), ALCELL^® lignin has been used in phenol-formaldehyde resin adhesive

' formulations.

SUMMARY OF THE INVENTION

This invention provides for adhesives for wood composites comprising an organosolv lignin and a phenol- formaldehyde resin in a weight ratio of from about

0.5:99.5 to about 70:30 based on phenolic solids in said phenol-formaldehyde resin.

In accordance with this invention, the performance of the adhesive can be improved by the addition of a modifier in a weight ratio with organosolv lignin of from about 0.5:99.5 to about 20:80. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, the performance of the adhesive can be improved by the addition of a low molecular weight organosolv lignin in a weight ratio with organosolv lignin of from about 5:95 to about 70:30. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, the performance of the adhesive can be improved by extending the press time or increasing the press temperature during board manufacture. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, the performance of the adhesive can be improved by baking and -drying the organosolv lignin prior to formulation. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, a liquid phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 3 and alkali of from about 0.12 to about 0.47 moles per mole of phenol. An adhesive can be manufactured comprising organosolv lignin of from about 5:95 to 60:40 based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, a liquid phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol. An adhesive can be manufactured comprising organosolv lignin of from about 0.5 to about 40% based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, a liquid phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.3 to about 3.0, alkali of from about 0.5 to about 0.8 moles per mole of phenol. An adhesive can be manufactured comprising organosolv lignin from about 2 to about 30% based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, a liquid phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.4 to about 3.5 and alkali of from about 0.4 to about 1 moles per mole of phenol. An adhesive can be manufactured comprising organosolv lignin from about 0.8 to about 35% based on phenolic solids in said phenol-formaldehyde resin. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, low molecular weight organosolv lignin can be used as a partial replacement for phenol in the manufacture of a liquid phenol-formaldehyde resin. The low molecular weight organosolv lignin can be added during the preparation of the resin and replace from about 0.5 to about 40% of the phenolic resin solids in the adhesive. The phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole^' ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, an alkaline solution of an organosolv lignin can be used as a partial replacement for phenol during the manufacture of a liquid phenol-formaldehyde resin. The alkaline solution of organosolv lignin can be prepared by addition of alkali of from about 10 to about 25% on a lignin weight basis and can be added to a liquid phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on phenolic solids in the resin. The phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 3 and alkali of from about 0.12 to about 0.47 moles per mole of phenol. Boards manufactured ^~ with this particular adhesive have competitive properties.

In accordance with this invention, the alkaline solution of organosolv lignin can be used as a partial replacement for phenol during the manufacture of a liquid phenol-formaldehyde resin and replace from about 2 to about 30% of the phenolic resin solids. The phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.3 to about 3 and alkali of from about 0.5 to about 0.8 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, an organosolv lignin dispersion can be added to a liquid phenol- formaldehyde resin. The dispersion comprises a dispersing agent and organosolv lignin in a weight ratio of from about 0.5:99.-5 to about 2:98. The organosolv lignin dispersion can be directly added to the resin in a weight ratio of from about 5:95 to about 60:40 based on phenolic solids in the resin. The phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 3 and alkali of from about 0.12 to about 0.47 moles per mole of phenol. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, the organosolv lignin dispersion comprising a dispersing agent and organosolv lignin in a weight ratio of from about 0.5:99.5 to about 5:95 can be added to a phenol-formaldehyde resin comprising organosolv lignin as a partial replacement for phenol. The organosolv lignin can be copolymerized during the condensation reaction of phenol and formaldehyde and can replace from about 0.5 to about 40% of the phenolic resin solids in the resulting adhesive. The phenol- formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2 to about 4.5 moles of formaldehyde per mole of phenol and alkali in a mole ratio of from about 0.1 to about 0.8 per mole of phenol. Boards manufactured _with this particular adhesive have competitive properties.

In accordance with this invention, organosolv lignin can be phenolated ' by reacting the organosolv lignin of from about 10 to about 80% of total reaction weight with phenol of from about 10 to about 80% of total reaction weight with alkali of from about 1 to about 20% of total reaction weight. The phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol. The organosolv lignin can constitute for from about 1 to about 45% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, organosolv lignin can be phenolated by reacting the organosolv lignin of from about 10 to about 80% of total reaction weight with phenol of from about 10 to about 80% of total reaction weight with alkali of from about 1 to about 20% of total reaction weight. The phenol-formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.4 to about 3.5 and alkali of from about 0.4 to about 1 moles per mole of phenol. The organosolv lignin can constitute from about 1 to about 70% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, organosolv lignin can be methylolated by reacting the organosolv lignin of from about 20 to about 60% of total reaction weight with phenol of from about 20 to about 50% of total reaction weight. Formaldehyde of from about 5 to about 50% of total reaction weight can be added using an acid of from about 0.01 to about 3% of total reaction weight. The phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2 to about 4.5 and alkali of from about 0.1 to about 0.8 moles per mole of phenol. The organosolv lignin can constitute from about 1 to about 70% on a phenol weight basis. Boards manufactured with - this particular adhesive have competitive properties.

In accordance with this invention, organosolv lignin can be methylolated by reacting the organosolv lignin of from about 20 to about 60% of total reaction weight with phenol of from about 20 to about 50% of total reaction weight. Formaldehyde of from about 5 to about 50% of total reaction weight can be added using an acid of from about 0.01 to about 3% of total reaction weight. The phenol- formaldehyde resin can be manufactured with a formaldehyde to phenol mole ratio of from about 2.4 to about 3.5 and alkali of from about 0.4 to about 1 moles per mole of phenol. The organosolv lignin can constitute from about I to about 45% on a phenol weight basis. Boards manufactured with this particular adhesive have competitive properties.

In accordance with this invention, methylolated organosolv lignin or alternatively low molecular weight organosolv lignin can be used in the manufacture of an adhesive for particleboard applications. The organosolv lignin can be reacted with formaldehyde and a resin can be prepared with formaldehyde to lignin weight ratio of from about 5:95 to about 50:50. The reaction can be carried out under alkaline conditions with alkali to lignin weight ratio from about 10:90 to about 40:60.

In accordance with this invention, organosolv lignin and organosolv lignin-based wood adhesives can be effective binders for cellulosic fibers present in waste paper and wood waste. The lignin can be used as a powder, as a dispersion or as an alkaline solution with or without methylolation. Lignin based resins in which lignin has been copolymerized as a partial replacement for phenol can also be used.

In accordance with another aspect of this invention, molded products can also be manufactured from cellulosic fibers-based materials, organosolv lignin or lignin-based wood adhesives. The organosolv lignin and cellulosic fibers-based materials can be blended in a weight ratio of from about 2:98 to about 20:80 organosolv lignin to cellulosic fibers with optional addition of wax such as the ratio of wax to cellulosic fiber is from about 1:99 to about 25:75. By pressing the resulting blend, a molded product can be obtained.

These and other details of the invention will be apparent from a reading of the remainder of this specification and the claims.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The lignin employed in this invention is an organosolv lignin, preferably ALCELL^® lignin which is the natural product extracted from wood with alcohol and water and is recovered as described in U.S. Patent No. 4,764,596 and ϋ.S. Patent Applications Ser. No. 07/649,683 filed February 1, 1991 and Ser. No. 08/011,329, filed January 29, 1993 and incorporated by reference herein. ALCELL® lignin is recovered as a free-flowing powder and resembles to a great extent native lignin.

In the present invention, organosolv lignin such as ALCELL^® lignin- can be added in a variety of ways as a substitute for phenol-formaldehyde core and face resins which are suitable in the formulation of adhesives for use in the manufacture of wood composites such as structural and nonstructural wood products including plywood, waferboard, oriented strandboard, particleboard, fiber board, hardboard, molded wood products and the like.

ALCELL^® lignin is sulfur-free and has low levels of carbohydrates and inorganic contaminants. It is also highly hydrophobic, is essentially insoluble in neutral or acidic aqueous media, and is soluble in moderate to strong alkaline solutions and certain organic solvents.

ALCELL^® lignin can be characterized as having: a relatively low number average molecular weight of about 800 to 1500 g/mole, preferably about 900 to 1300 g/mole and a glass transition temperature which is preferably about 100° to 170°C, particularly about 130° to 150°C, although a glass transition temperature of preferably about 80° to 170°C, particularly about 90° to 150°C is also observed; a narrow molecular weight distribution, i.e., a polydispersity of less than about 4, preferably no more than about 3, particularly only about 1.5 to 2.7; and, a methoxyl content approximately equal to the methoxyl content of native lignin (i.e., about 20% for hardwoods and about 14% for softwoods). ALCELL® lignin also has a softening temperature which is preferably about 120° to 150°C, particularly about 130° to 150°C.

In a preferred embodiment, in waferboard and oriented strandboard manufacture, powder phenol-formaldehyde resin and dry organosolv lignin are directly blended in a weight ratio of from about 30:70 to about 95:5, preferably of from about 70:30 to about 85:15.

The performance of the combination of dry organosolv lignin and powder phenol-formaldehyde resin can be further improved by extending the press time or by increasing the press temperature. Alternatively, baking the organosolv lignin for from about 15 to about 90 minutes and at temperatures of from about 120 to about 200°C or flash drying of the organosolv lignin at a dryer inlet temperature of from about 135° to about 250°C prior to formulation, significantly improves board properties. The performance of the organosolv lignin/phenol- formaldehyde resin combination can be improved by the addition of a modifier, preferably of a phenolic nature. Modifiers such as low molecular weight phenolic compounds, phenol, or low molecular weight ALCELL^® lignin can be used. Other modifiers which can be used include tris-(p- hydroxyphenyl) ethane (THPE), p-tert-butyl-phenol (PTBP), bisphenol-A (BPA), p-cresol, p-ethylphenol, p-sec- butylphenol, p-amylphenol, p-nonylphenol, p-dodecylphenol, 2,4-dimethylphenol, 2,4,6,-trimethylphenol, para-alkyl phenols with side chains of 18 to 24 and 24 to 28 carbons, polyhydroxystyrene, creosote blends and furfural which comprises washed ALCELL^® furfural recovered in the process described in U.S. Patent Application Ser. No. Ser. No. 07/ 649,683 filed February 1, 1991 and Patent Application Ser. No. 08/011,329 filed January 29, 1993 and incorporated herein by reference.

The modifier can be directly added to the powder phenol-formaldehyde resin and the dry organosolv lignin. A modifier such as phenol, p-tert-butylphenol (PTBP) and bisphenol-A (BPA) and furfural can be added in a modifier to organosolv lignin weight ratio of from about 0.5:99.5 to about 20:80, preferably 1:99 to 10:90. The combination of organosolv lignin and modifier can substitute for from about 15 to about 75% of the phenolic resin solids_.

Low molecular weight ALCELL^® lignin can also be added to the organosolv lignin as a modifier in a weight ratio of from about 5:95 to about 70:30, preferably 20:80 to 50:50. Low molecular weight ALCELL^® lignin is recovered as a tarry precipitate in the process described in U.S. Patent Application Serial No. 07/649,683 filed February 1, 1991 and Patent Application Serial No. 08/011,329 filed January 29, 1993. Low molecular weight ALCELL^® lignin can be characterized by a low number average molecular weight in the range of less than 500 g/mole and a low glass transition temperature in the range of from about 24° to about 80°C. Another characteristic, when hardwoods are pulped, is that the low molecular weight ALCELL^® lignin is predominantly of the syringyl type, since by nitrobenzene oxidation, it yields a syringaldehyde to vanillin molar ratio of from about 2.7:1 to about 5.3:1. The low molecular weight ALCELL^® lignin can be dried first then can be added to the organosolv lignin or alternatively, the low molecular weight ALCELL^® lignin and the organosolv lignin can be mixed first then dried simultaneously prior to use.

In another preferred embodiment, in waferboard and oriented strandboard manufacture, the dry organosolv lignin can be directly added to a liquid phenol- formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of dry organosolv lignin and dry solids in the phenolic resin. The phenol- formaldehyde resin can be prepared by condensation of formaldehyde and phenol in a mole ratio of from about 2 to about 3.0, preferably 2.2 to 2.5. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.12 to about 0.47, preferably 0.15 to^).3 moles of alkali per mole of phenol. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde. After resin formulation, the organosolv lignin and phenol-formaldehyde resin can be sequentially used to cover the wafers covered with about 1% by weight (based on solids of a wax emulsion) in a weight ratio of from about 2 to about 5% (resin solids to dry wafers). In another preferred embodiment, in particleboard applications, dry organosolv lignin can be directly blended into particle board furnish. The particleboard furnish was blended with wax from about 1 to about 3% wax solids on oven dried furnish and organosolv lignin at from about 5 to about 15% on furnish. The resulting blend was processed into panels using standard temperatures and pressures commonly used in panel manufacture. Panels have properties in conformity with standard specifications for several applications.

In another preferred embodiment, in waferboard and oriented strandboard manufacture, the organosolv lignin can be copolymerized during the condensation reaction of phenol and formaldehyde and can replace from about 0.5 to about 40%, preferably from about 5 to about 30% of the phenolic resin solids in the resulting adhesive. The phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2 to about 4.5, preferably from about 2.2 to about 4.2 moles of formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol. The organosolv lignin can be added in an amount sufficient to constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde. The lignin/phenol- formaldehyde resin mixture can be blended with the wafers covered with about 1% by weight (based on solids of a wax emulsion) in a weight ratio of from about 2 to about 5% (resin solids to dry wafers).

In other applications, the organosolv lignin can be used as a partial replacement of phenol-formaldehyde resin used in plywood adhesive formulation. In a preferred embodiment, the phenol-formaldehyde resin can be prepared with a formaldehyde to phenol ratio of from about 2.3 to about 3.0, preferably from about 2.4 to about 2.6. The polymerization can be carried out under alkaline conditions in one or more alkali additions and preferably using sodium or potassium hydroxide, with a mole ratio of from about 0.5 to about 0.8, preferably of from about 0.65 to about 0.75 moles of alkali per mole of phenol. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde. The organosolv lignin can be added to the resin during adhesive preparation and replace from about 2 to about 30%, preferably from about 15 to about 20% of the phenolic resin solids.

In another preferred embodiment, in plywood adhesive formulation, the organosolv lignin can be copolymerized during resin manufacture and replace from about 0.8 to about 35%, preferably from about 4 to about 20% of the phenolic resin solids in the resulting adhesive. The phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2.4 to about 3.5, preferably from about 2.8 to about 3.1. The polymerization can be carried out under alkaline conditions, preferably using sodium or potassium hydroxide in one or more alkali additions with a mole ratio of from about 0.4 to about 1, preferably of from about 0.65 to about 0.85 moles of alkali per mole of phenol. The organosolv lignin can be added in a weight ratio with phenol of from about 2 to about 45%, preferably of from about 10 to about 30%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde. The resulting resin can be used during adhesive preparation.

In another preferred embodiment, low molecular weight organosolv lignin such as ALCELL^® lignin can be used as a partial replacement for phenol in the manufacture of a phenol-formaldehyde resin for waferboard and oriented strandboard applications. The low molecular weight organosolv lignin can be copolymerized during the condensation reaction of phenol and formaldehyde and replace from about 0.5 to about 40%, preferably from about 5 to about 30% of the phenolic resin solids in the resulting adhesive. The phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2 to about 4.5, preferably from about 2.2 to about 4.2 moles of formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol. The low molecular organosolv lignin can be added in an amount sufficient to constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another preferred embodiment, an alkaline solution of organosolv lignin can be added as a partial replacement for phenol during the synthesis of a phenol- formaldehyde resin for waferboard and oriented strandboard applications. An alkaline solution of organosolv lignin can be prepared using the organosolv lignin cake prior to drying or the organosolv lignin powder after drying recovered from the pulping processes described herein. An alkaline solution can also be prepared using the low molecular weight ALCELL^® lignin. In a preferred embodiment, alkali for example sodium or potassium hydroxide can be added in one or more additions in an amount of from about 10 to about 25%, preferably from about 12 to about 22% on a lignin weight basis. Water can be added as needed such that total solids are from about 30% to about 50%, preferably of from about 35% to about 45%. The organosolv lignin can be added slowly with agitation. The resulting organosolv lignin alkaline solution can be added to a liquid phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of dry organosolv lignin and dry solids in the phenolic resin. The phenol-formaldehyde resin can be prepared by condensation of formaldehyde and phenol in a mole ratio of from about 2 to about 3.0, preferably from about 2.2 to about 2.5. The polymerization can be carried out under alkaline conditions, for example using sodium orjpotassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.12 to about 0.47, preferably from about 0.15 to about 0.3 moles of alkali per mole of phenol. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another preferred embodiment, the alkaline organosolv lignin solution can be added to a phenol- formaldehyde resin for plywood applications. The organosolv lignin alkaline solution can be added to a phenol-formaldehyde resin during adhesive preparation and replace from about 2 to about 30%, preferably from about 15 to about 20% of the phenolic resin solids in the resulting adhesive. The phenol-formaldehyde resin can be prepared with a formaldehyde to phenol ratio of from about 2.3 to about 3.0, preferably from about 2.4 to about 2.6. The polymerization can be carried out under alkaline conditions in one or more alkali additions and preferably using sodium or potassium hydroxide, with a mole ratio of from about 0.5 to about 0.8, preferably of from about 0.65 to about 0.75 moles of alkali per mole of phenol. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another preferred embodiment, an organosolv lignin dispersion can be prepared and can be blended with a phenol-formaldehyde liquid resin for waferboard and oriented strandboard applications. Surfactants such as sodium and ammonium polymethacrylate, alkaline compounds such as sodium hydroxide, ammonium hydroxide, magnesium hydroxide and preferably calcium hydroxide can also be used. Other compounds which have a dispersant effect on the organosolv lignin including amines such as for example monoethanolamine and diethanolamine can also be used as a dispersing agent-.

The organosolv lignin cake prior to drying or the organosolv lignin powder after drying recovered from the pulping processes referred to herein can be used. Similarly, low molecular weight ALCELL^® lignin can also be used. In a preferred embodiment, the dispersing agent can be added to water and the organosolv lignin can be added slowly with agitation and the level of dispersing agent and organosolv lignin adjusted so that the dispersion behaves thixotropically. The solids content of the dispersion are in the range of from about 45 to about 65%, preferably in the range of from about 50 to about 55%. The weight ratio of dispersing agent to organosolv lignin can be from about 0.5:99.5 to about 5:95, preferably from about 1:99 to about 1.5:98.5. The organosolv lignin dispersion can be directly added to a liquid phenol- formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of dry organosolv lignin and dry solids in the phenolic resin. The phenol- formaldehyde resin can be prepared by condensation of formaldehyde and phenol in a mole ratio of from about 2 to about 3.0, preferably from about 2.2 to about 2.5. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.12 to about 0.47, preferably from about 0.15 to about 0.3 moles of alkali per mole of phenol. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another preferred embodiment, an organosolv lignin dispersion was blended with a phenol-formaldehyde resin comprising organosolv lignin as a partial replacement for phenol. The organosolv lignin can be copolymerized during the condensation reaction of phenol and formaldehyde and can replace from about 0.5 to about 40%, preferably from about 5 to about 30% of the phenolic resin solids in the resulting adhesive. The phenol-formaldehyde resin can be prepared with formaldehyde to phenol mole ratio of from about 2 to about 4.5, preferably from about 2.2 to about 4.2 moles of formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions and in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol. The organosolv lignin can be added in an amount sufficient to constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde. The organosolv lignin dispersion can be manufactured as described above and comprises a dispersing agent and organosolv lignin in a weight ratio of from about 0.5:99.5 to about 2:98. The organosolv lignin dispersion can be directly added to the resin in a weight ratio of from about 5:95 to about 60:40 based on phenolic solids in the resin.

In another preferred embodiment, phenolation of organosolv lignin can be used in the manufacture of a phenol-formaldehyde resin for waferboard and oriented strandboard applications. Phenolation of organosolv lignin can be achieved by reacting organosolv lignin from about 10 to about 80%, preferably of from about 30 to about 60% of total reaction weight with phenol of from about 10 to about 80%, preferably of from about 20 to about 60% of total reaction weight under alkaline conditions, using sodium or potassium hydroxide in one or more alkali additions of from about 1 to about 20%, preferably from about 5 to about 10% of total reaction weight at a temperature of from about 80° to about 200°C, preferably of from about 110° to about 180° C and for from about 0.5 to about 2 hours, preferably from about 0.5 to about 1.5 hours. The phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2 to about 4.5, preferably of from 2.2 to about 4.2 moles formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in -one or more alkali additions in a mole ratio of from about 0.1 to about 0.8, preferably of from about 0.2 to about 0.75 moles of alkali per mole of phenol. The phenolated organosolv lignin can constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Enough water can be added such that the total solids in the resin are about 57%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another preferred embodiment, phenolation of organosolv lignin can be used in the manufacture of a phenol-formaldehyde resin for plywood applications. Phenolation of organosolv lignin can be achieved by reacting organosolv lignin of from about 10 to about 80%, preferably of from about 30 to about 60% of total reaction weight with phenol of from about 10 to about 80%, preferably of from about 20 to about 60% of total reaction weight under alkaline conditions, using sodium or potassium hydroxide of from about 1 to about 20%, preferably from about 5 to about 10% of total reaction weight at a temperature of from about 80 to about 200°C, preferably of from about 110° to about 180° C and for about 0.5 to about 2 hours, preferably from about 0.5 to about 1.5 hours. The phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2.4 to about 3.5, preferably of from 2.8 to about 3.1 per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.4 to about 1, preferably from about 0.65 to about 0.85 moles of alkali per mole of phenol. The phenolated organosolv lignin can constitute from about 1 to about 45%, preferably from about 10 to about 30% on a phenol weight basis. Enough water can be added such that the total solids in the resin are about 42%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another embodiment, organosolv lignin can be methylolated by acid catalysis and the methylolated organosolv lignin can be used in the manufacture of adhesives for waferboard and oriented strandboard applications. Methylolation can be incorporated as a first step during the manufacture of the phenol-formaldehyde liquid resin. To promote solubility under acidic conditions, the organosolv lignin can be solubilized using a solvent which can be used in phenol-formaldehyde resin manufacture. A solvent such as trioxane, phenol or other phenolic compounds can be used. Organosolv lignin of from about 2 to about 60%, preferably from about 20 to about 40% of total reaction weight is dissolved in phenol of from about 20 to about 50%, preferably of from about 30 to about 45% of total reaction weight. Formaldehyde of from about 5 to about 50%, preferably of from about 10 to about 30% of total reaction weight is added under acidic conditions using a mineral or organic acid, preferably using sulfuric acid of from about 0.01 to about 3%, preferably of from about 0.1 to about 2% of total reaction weight. The mixture is heated to from about 40 to about 100°C, preferably to from about 60 to about 90°C for about 30 to about 180 minutes, preferably for about 60 to about 120 minutes. The phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2 to about 4.5, preferably of from 2.2 to about 4.2 moles formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.1 to about 0.8, preferably from about 0.2 to about 0.75 moles of alkali per mole of phenol. The organosolv lignin can constitute from about 1 to about 70%, preferably from about 10 to about 50% on a phenol weight basis. Enough water can be added such that the total solids in the resin are about 57%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

Similarly, acid methylolation of organosolv lignin can also be used in the manufacture of adhesive for plywood applications. Organosolv lignin of from about 2 to about 60%, preferably from about 20 to about 40% of total reaction weight is dissolved in phenol of from about 20 to about 50%, preferably of from about 30 to about 45% of total reaction weight. Formaldehyde of from about 5 to about 50%, preferably of from about 10 to about 30% of total reaction weight is added under acidic conditions using a mineral or organic acid, preferably using sulfuric acid of from about 0.01 to about 3%, preferably of from about 0.1 to about 2% of total reaction weight. The mixture is heated to from about 40 to about 100°C, preferably to from about 60 to about 90°C for about 30 to about 180 minutes, preferably for about 60 to about 120 minutes. The phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2.4 to about 3.5, preferably of from 2 to about 3.1 moles formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.4 to about 1, preferably from about 0.65 to about 0.85 moles of alkali per mole of phenol. The organosolv lignin can constitute from about 1 to about 45%, preferably from about 10 to about 30% on a phenol weight basis. Enough water can be added such that the total solids in resin are about 42%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another embodiment, methylolation of either organosolv lignin or alternatively low molecular weight organosolv lignin can be used in the manufacture of adhesive in particleboard applications. It is believed that methylolated low molecular weight organosolv lignin is more effective due to its lower viscosity at a given solids concentration. Thus, it is believed that higher solids content binders can be prepared which tends to accelerate resin curing. The particleboard manufactured with the methylolated organosolv lignin and methylolated low molecular weight organosolv lignin have the distinct advantage that they are not manufactured using urea- formaldehyde resins thereby avoiding the release of formaldehyde during the life of the particleboard panel. In a preferred embodiment, the organosolv lignin can be reacted with formaldehyde and a resin can be prepared with formaldehyde to lignin weight ratio of from about 5:95 to about 50:50, preferably from about 20:80 to about 30:70. The reaction can be carried out under alkaline conditions, preferably using sodium or potassium hydroxide in one or more alkali additions. When sodium hydroxide is used, the alkali to lignin weight ratio is from about 10:90 to about 40:60, preferably of from about 12:88 to about 25:75. The mixture is heated to from about 40 to about 100°C, preferably to from about 60 to about 90°C for about 30 to about 180 minutes, preferably for about 60 to about 120 minutes. The phenol-formaldehyde resin can be prepared by addition of more phenol, if required, and formaldehyde such that the molar ratio of formaldehyde to phenol is from about 2.4 to about 3.5, preferably of from 2 to about 3.1 moles formaldehyde per mole of phenol. The polymerization can be carried out under alkaline conditions, for example using sodium or potassium hydroxide in one or more alkali additions in a mole ratio of from about 0.4 tq_Ξabout 1, preferably from about 0.65 to about 0.85 moles-of-alkali per mole of phenol. The organosolv lignin can constitute from about 1 to about 45%, preferably from about 10 to about 30% on a phenol weight basis. Enough water can be added such that the total solids in resin are about 42%. Urea, ammonia or other suitable compound can be added in an amount sufficient to react with any excess formaldehyde.

In another embodiment of the invention, organosolv lignin and organosolv lignin wood adhesives can be effective binders for cellulosic fibers in general and more particularly for cellulosic fibers present in waste paper including post-consumer waste or manufacturing scrap (e.g. newsprint, corrugated containers, coated paper and cardboard boxes, and the like) and cellulosic fibers present in wood waste such as for example wood residues from demolition products. The lignin can be used as a powder, as a dispersion or as an alkaline solution with or without methylolation. Lignin based resins in which lignin has been copolymerized as a partial replacement for phenol can also be used.

Other applications involving the binding of cellulosic fibers using organosolv lignin and lignin-based wood adhesives include boards for interior paneling, floor underlayment, ceiling panels, acoustic panels and insulating panels. These panels can have different types of facing, for example, laminated vinyl, wood veneers, aluminum foil, plastics, hardboard, oriented strandboard and paper laminates.

Molded products can also be manufactured from cellulosic fibers-based materials and organosolv lignin. Cellulosic fibers-based materials such as for example waste paper can be used. Molded products can be of various shapes and include one-piece pallets and pallet components, doors and door facings, trim moldings, interior paneling for automobiles, one-piece packaging containers degradable plant pots and the like. The organosolv lignin and cellulosic fibers-based materials can be blended in a weight ratio of from about 2:98 to about 20:80, preferably 5:95 to about 15:85 organosolv lignin to cellulosic fibers with optional addition of wax such as the ratio of wax to cellulosic fiber is from about 2:98 to about 10:90, preferably 3:97 to about 7:93. By pressing the resulting blend, a molded product can be obtained. In a preferred embodiment, shredded paper from for example newspaper, polyethylene coated paperboard and publication grade coated paper can be blended with from about 2 to about 20% wax, for example Paracol 2370 and organosolv lignin such as ALCELL^® lignin of from about 8 to about 15%. The resulting blend can be pressed between two forming plates for specified manufacturing conditions of time, pressure and temperature followed by a decompression. A molded product can be obtained which approximates the geometry of a one-piece pallet.

The foregoing can have applications to the manufacture of molded products using paperboard as a source of cellulosic fibers. When wax coated paperboard is used, significant environmental benefits can result as wax coated paperboard is believed not to be amenable to recycling because of its high wax content which is typically 50%.

In use of the adhesives, the various known methods and procedures used in the manufacture of wood composites can be employed. The conditions of manufacture are within the conditions presently used with the variations normally encountered and obvious to those skilled in the art.

The wood composites of the invention are manufactured using standard manufacturing procedures and techniques except where specifically noted. Tables 1, 2, 3, 4 and 5 illustrate the parameters used in the manufacture of the wood composites of the invention including novel adhesive formulation techniques and methods, as more particularly set forthj.n the following examples.

EXAMPLE 1

Table 6 shows the physical properties of boards made by substituting about 20% of a particular powder phenol-formaldehyde resin BAKELITE 9111 (manufactured by Bakelite Ther osets Limited, Belleview, Ontario, Canada) blended with different dry lignins. The boards were manufactured according to the parameters in Table 1. The results in Table 6 indicate that organosolv lignin such as ALCELL^® lignin was the best substitute in terms of improving board properties. EXAMPLE 2

When dry ALCELL^® lignin was intermixed as a partial substitute with a powder phenol-formaldehyde face resin such as GP5415 (manufactured by Georgia Pacific, Crossett, AK), improved board properties as shown in Table 7 demonstrate that ALCELL^® lignin was particularly compatible with GP5415. The waferboard were manufactured according to the parameters in Table 3.

EXAMPLE 3

In this example, about 50% of a powder phenol- formaldehyde resin (e.g. BD909) was substituted with an ALCELL^® lignin and a modifier such as phenol. About nine parts of dry ALCELL^® lignin in about ten parts of water was mixed with about one part of phenol. The mixture was air dried into a powder then used to substitute for about 50% of a phenol-formaldehyde resin. Waferboard were manufactured according to the parameters in Table 1. The results in Table 8 indicate that the performance of the combination of dry ALCELL^® lignin and a phenol- formaldehyde resin was improved by a modifier such as phenol and superior board properties were obtained.

EXAMPLE 4

When about 2% phenol based on total adhesive weight was added to dry ALCELL^® lignin and the mixture was blended with resin GP5415 following the procedure of Example 3, the results in Table 9 show that superior board properties were obtained relative to those obtained with un-modified ALCELL^® lignin/GP5415 resin combination. A similar improvement in board properties was also observed with the ALCELL® lignin/BD023 and ALCELL^® lignin/BD802 adhesive systems made as in Example 3. Waferboard were manufactured according to the parameters in Table 1.

EXAMPLE 5

Similarly, a modifier such as low molecular weight ALCELL^® lignin can be used to improve the performance of organosolv lignin such ALCELL^® lignin with for example a phenol-formaldehyde resin such as BD909 as shown in Table 10. The tarry low molecular weight ALCELL^® lignin was added to the ALCELL^® lignin in the proportions shown in Table 10, and the mixture was heated to about 120°C. The mixture was cooled to about 25°C and ground into a powder. The powder was blended with a phenol- formaldehyde resin such as BD909. The waferboard were manufactured using the parameters in Table 1.

EXAMPLE 6

In this example, about 20% of a powder phenol- formaldehyde resin (e.g. BD909 and GP5478) was substituted with an ALCELL^® lignin and a modifier such as tris-(p-hydroxyphenyl) ethane (THPE), bisphenol-A (BPA), p-tert-butylpheno__ (PTBP), p-cresol, p-nonylphenol, para- alkyl phenol with a side chain of 18 to 24 carbons, 2,4- dimethylphenol, 2,4,6-trimethylphenol and ALCELL^® furfural. About nine parts of dry ALCELL^® lignin in about ten parts of water were mixed with about one part of modifier as in Example 3. The mixture was air dried into a powder then used to substitute for about 20% of the phenol-formaldehyde resin. Waferboard were manufactured according to the parameters in Table 4 with board thickness of 3/8" and when ALCELL^® furfural was used as a modifier, a press time of 240 seconds. The results in Tables 11 and 12 indicate that the performance of ALCELL^® lignin was improved by the modifiers of Tables 11 and 12.

EXAMPLE 7

In this example, about 20% of a powder phenol- formaldehyde resin (e.g. GP5479) was substituted with an ALCELL® lignin and a modifier such as p-tert-butylphenol (PTBP). In this example, a dry blend of the modifier was prepared by grinding the modifier to a particle size close to the particle size of ALCELL^® lignin. The dry ALCELL^® lignin and the modifier were combined into dry blends containing about 1, about 4 and about 10% of the modifier on a total blend weight basis. Waferboard were manufactured according to the parameters in Table 4. The results in Table 13 indicate that the modifiers effectively increase the compatibility of the ALCELL^® lignin and superior board properties were obtained.

EXAMPLE 8

The results in Table 14 indicate that the performance of the combination of a dry organosolv lignin such as ALCELL^® lignin blended with a powder phenol- formaldehyde resin such as BD909 can be improved by increasing the press time to about 200 seconds or longer at a press temperature of about 400°F. Results in Table 14 how improved board properties. The waferboard were manufactured according to the parameters in Table 3. EXAMPLE 9

The performance of the combination of a dry organosolv lignin such as ALCELL^® lignin with a powder phenol-formaldehyde resin such as BD909 can also be improved by increasing the press temperature to about 415°F while keeping the press time constant at about 170 seconds as shown in Table 15. Waferboard were manufactured according to the parameters in Table 3.

EXAMPLE 10

In this particular example, when dry ALCELL® lignin was baked at a temperature of about 160° C and for about 60 minutes and then was blended with a powder phenol-formaldehyde resin such as BD909, a significant improvement in board properties was observed, as shown in Table 16. Waferboard were manufactured according to the parameters in Table 1.

EXAMPLE 11

When ALCELL^® lignin was flash dried at a dryer inlet temperature of from about 138° to about 235°C, then was blended with a powder phenol-formaldehyde resin such as BD909 as shown in Table 17. Improved board properties were obtained. Waferboard were manufactured according to the parameters in Table 1.

EXAMP E 12

This example illustrates the procedure followed in the preparation of a liquid phenolic resin used to formulate a liquid adhesive for waferboard applications. About one mole of phenol, about 2.2 moles of formaldehyde and about 0.2 moles of sodium hydroxide were reacted and the polymerization was carried forward at a temperature of from about 80° to 100°C, and until a viscosity of about 250 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below. The final resin composition was about 57% total solids and the viscosity was about 200 cps (measured at 25°C).

EXAMPLE 13

In this example, the organosolv lignin was directly added to the condensation reaction mixture of phenol and formaldehyde and copolymerized during such reaction. Subsequently, this resin was used to formulate a liquid adhesive for waferboard applications. About 2.7 moles of formaldehyde, about 0.05 moles sodium hydroxide and about 20% ALCELL^® lignin on a weight basis with phenol were reacted for about 90 minutes at a temperature of about 70°C. The reaction mixture was cooled to about 30°C, and about one mole of phenol and about 0.2 moles of sodium hydroxide were added. The mixture was then heated to about 80°C and polymerization was continued until a target viscosity of from about 200 to about 700 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below. The lignin/ phenolic resin composition was about 57% total solids of which about 12% was organosolv lignin. EXAMPLE 14

In this example, wood wafers (e.g. Aspen) were placed in a rotating blender and about 1% (w/w) of a wax emulsion (e.g. PARACOL 802N manufactured by Hercules, Wilmington, DE) was sprayed to cover the wafers. Organosolv lignin, such ALCELL^® lignin in dry form and the liquid phenol-formaldehyde resin of Example 12 were used to cover the wafers in a weight ratio of about 20:80, the organosolv lignin was used to cover the wafers prior to spraying with liquid phenol-formaldehyde resin. The total phenol-formaldehyde resin and organosolv lignin solids were blended on the wafers at about 4.5% (w/w).

EXAMPLE 15

The mixture of wafers of Example 14 containing about 3.6% Example 12 liquid phenol-formaldehyde resin and about 0.9% dry ALCELL^® lignin were pressed into 3/8" boards at a temperature of about 410°F, at a pressure of about 540 psig and for about 5 minutes and according to the manufacturing parameters of Table 2. These waferboard were compared to control boards manufactured with about 4.5% Example 12 liquid phenol-formaldehyde resin and no ALCELL® lignin. The results in Table 18 show that the ALCELL® lignin containing boards have good properties and were competitive with control boards.

EXAMPLE 16

In this example, two batches of wood wafers were made according to the procedure of Example 14 without the addition of dry ALCELL^® lignin. The wafers in each batch contain about 4.5% of Example 13 liquid phenol- formaldehyde resins at about 390 cps and at about 700 cps viscosity. The wafers were pressed into 3/8" boards at a temperature of about 410°F, at a pressure of about 540 psig and for about 5 minutes and according to the manufacturing parameters of Table 2. These waferboard were compared to control boards manufactured with about 4.5% Example 12 liquid phenol-formaldehyde resin and no ALCELL® lignin. The results in Table 19 show that the ALCELL® lignin containing boards have good properties and were competitive with control boards.

EXAMPLE 17

This example illustrates the procedure followed in the preparation of a liquid phenol-formaldehyde resin for plywood applications. The organosolv lignin was added to the liquid phenol-formaldehyde resin during ___ plywood adhesive formulation (see Example 20). About one mole of phenol, about 2.45 moles of formaldehyde, the water and a first portion of the sodium hydroxide, preferably about 0.15 moles sodium hydroxide per mole of phenol were reacted at a temperature of from about 80° to 100°C until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. A second portion of the sodium hydroxide, preferably about 0.2 moles were added and the polymerization was carried forward at a temperature of from about 65° to 75°C, and until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. A third portion of sodium hydroxide, preferably 0.15 moles were added and the reaction was continued at a temperature of from about 65° to 75°C until a viscosity of from about 1500 to 1800 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below. The final resin composition was about 42% total solids and the resin viscosity was about 800 cps (measured at 25°C).

EXAMPLE 18

In this example, the organosolv lignin was directly added to the condensation reaction mixture of phenol and formaldehyde and copolymerized during such reaction. The lignin-containing phenol-formaldehyde resin can be used to formulate an adhesive for plywood applications (see Example 19). About 15% ALCELL^® lignin on a weight basis with phenol, about 0.28 moles formaldehyde, about 20% of the water and about 0.08 moles of sodium hydroxide were -reacted for about 90 minutes at from about 55° to 60°C. The mixture was cooled to a temperature of about 30°C and one mole of phenol, about 0.17 moles sodium hydroxide and about 2.52 moles of formaldehyde and the remaining water were added and the polymerization was continued until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. The mixture was cooled to a temperature of from about 55° to 75°C, about 0.23 moles of sodium hydroxide were added and the polymerization was continued until a viscosity of from about 2000 to 2500 cps. About 0.17 moles of sodium hydroxide were added and the polymerization was continued until a viscosity of from about 1700 to 2000 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to react with the excess formaldehyde, and the resin was quickly cooled to about 25°C or below. The lignin/phenolic resin composition was about 42% total solids and the resin viscosity was about 1000 cps (measured at 25°C) . EXAMPLE 19

An adhesive for plywood manufacture can be prepared in a variety of ways and different techniques have been employed to formulate the adhesive depending on the application. In this particular example, about 7.11% by weight of Example 18 phenol-formaldehyde resin, about 21.35% by weight water, about 12.09% by weight of a mixture of additives (e.g. fillers or viscosity modifiers) and about 2.49% by weight alkali, preferably sodium hydroxide, were mixed for from about 5 to 15 minutes. The balance of Example 18 resin, about 56.93% by weight was added to the mixture. The final adhesive composition was from about 24 to 32% total solids of which about 1 to 7% was organosolv lignin. The final adhesive viscosity was about 5600 cps (measured at 25°C). A commercial adhesive using for example Canadian Reichhold Chemical Company BB- 055 Resin was prepared following a similar procedure.

EXAMPLE 20

An adhesive for plywood manufacture was prepared using the procedure of Example 19. In this example, about

13.62% by weight of Example 17 phenol-formaldehyde resin, about 18.54% by weight water, about 11.17% by weight of a mixture of additives (e.g. fillers or viscosity modifiers), about 3.07% by weight alkali, preferably sodium hydroxide, and about 4.78% organosolv lignin, preferably ALCELL^® -lignin were mixed for from about 5 to

15 minutes. The balance of Example 17 resin, about 48.81% by weight was added to the mixture. The final adhesive composition was from about 24 to 32% resin solids of which about 2 to 10% was organosolv lignin. The final adhesive viscosity was about 3780 cps (measured at 25°C) . EXAMPLE 21

In this example, about 4.7% organosolv lignin was added to a commercial adhesive (e.g. Borden 3130H) . About 13.60% of a commercial resin (e.g. Borden 3130), about 18.53% water, about 11.2% of a mixture of additives (e.g. fillers or viscosity modifiers), about 4.8% organosolv lignin, preferably ALCELL^® lignin and about 3.06% alkali, preferably sodium hydroxide were mixed for from about 5 to 15 minutes. The balance of the commercial resin, about 48.8% by weight was added to the mixture. The final adhesive composition was about 26.85% resin and about 4.7% organosolv lignin. The final adhesive viscosity was about 7200-cps (measured at 25°C) .

The following examples are illustrative of a testing procedure which compares the adhesion performance of the lignin-containing plywood adhesive of the invention with a commercial adhesive. The adhesives as prepared were particularly suited for use with Douglas Fir plywood and can be modified for other applications (e.g. by spray or mechanical spreader) and for use with other veneers (e.g. southern pine) . Test panels were prepared under extreme manufacturing conditions in order to accentuate the two major causes of panel failure, namely over-penetration and dry-out. Shear specimens were prepared and tested for over-penetration and dry-out according to an approved procedure (e.g. American Plywood Association, PS 1-83).

EXAMPLE 22

An adhesive for plywood manufacture was prepared using the procedure of Example 19. In this particular example, the plywood adhesive was suitable for commercial applications. In this example, about 13.62% by weight of Example 17 phenol-formaldehyde resin, about 19.11% by weight water, about 10.62% by weight of a mixture of additives (e.g. fillers or viscosity modifiers), about 3.11% by weight alkali, preferably sodium hydroxide, and about 4.82% organosolv lignin, preferably ALCELL^® lignin were mixed for from about 5 to 15 minutes. The balance of Example 17 resin, about 48.90% by weight was added to the mixture. The final adhesive composition was about 26.6% total solids of which about 4.82% was organosolv lignin. The final adhesive viscosity was about 7000 cps (measured at 25°C).

EXAMPLE 23

The adhesives in Table 20 were tested by the preparation of three ply panels made with 1/8" Douglas Fir veneer. The panels were pressed using a press temperature of about 300°F and a pressure of about 200 psi. To accentuate over-penetration, a wet glue spread of about 70 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of from about 2 to 3 minutes and a pressing time of about 6 minutes. To accentuate dry-out, a wet glue spread of about 40 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of about 40 minutes and a pressing time of about 5 minutes. The press was closed immediately after loading so that there was no "fry-time". The panels were tested using the vacuum pressure and four- hour alternate boil test and the results are summarized in Table 20. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. EXAMPLE 24

Three ply panels were prepared and tested as in Example 23. Results in Table 21 indicate that the adhesive of Example 20 performs better than commercial adhesives with or without lignin.

EXAMPLE 25

The adhesives in Table 22 were tested by the preparation of 13/16" five ply panels made with Douglas Fir veneer. In this example, the panels were pressed for varying press times, at a press temperature of about 300°F, and a pressure of about 200 psi. The wet glue spread was about 60 lbs of adhesive per 1,000 square feet of double glue line were used with an assembly time of about 15 minutes. The "fry-time" was about 0.5 minutes. The panels were tested using the vacuum pressure and four- hour alternate boil test and the results were summarized in Table 20. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 22 indicate that the organosolv lignin containing adhesive has the same or faster curing properties as the commercial adhesive.

EXAMPLE 26

The adhesive of Example 22 was tested in a commercial mill trial by the preparation of 5/6" three ply, 21/32" five ply and 25/32" five ply panels made with Douglas Fir veneer. The panels were cold pressed at a pressure of about 150 psi and for about 5 minutes, and hot pressed using a press temperature of about 275°F, a pressure of about 200 psi and for about 5.5 minutes. A wet glue spread of about 65 lbs of adhesive per 1,000 square feet of double glue line was used. The press was closed immediately after loading. The panels were tested using the vacuum pressure and four-hour alternate boil tests and the results were summarized in Table 23. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 23 indicate that Example 22 adhesive has excellent board properties.

EXAMPLE 27

In this example, ALCELL^® lignin dispersions were prepared and were blended with a phenol-formaldehyde resin to form the adhesive. In preparing the lignin dispersion, about 1.2% ammonium hydroxide (on ammonia basis) was used. Ammonium hydroxide was added to water and then ALCELL® lignin was added slowly with agitation to form a stable dispersion. The lignin dispersion contained about 51.3% total solids.

EXAMPLE 28

An adhesive for waferboard manufacture was prepared with the dispersion of Example 27. About 58.6 grams of the lignin dispersion of Example 27 was mixed with 214.4 grams of a phenol-formaldehyde resin (e.g. face resin PH-102) and 4.9 grams of water. The final adhesive composition was about 54% total solids of which about 20% was organosolv lignin. The final adhesive viscosity was about 379 cps (measured at 25°C). The final adhesive composition was adjusted by addition of water to about 50% total solids. The final adhesive viscosity was about 222 cps (measured at 25°C). EXAMPLE 29

The adhesive of Example 28 was tested by the preparation of boards manufactured according to the parameters of Table 5. The results of board testing were shown in Table 24 and demonstrate that the boards prepared were competitive with control boards.

EXAMPLE 30

In this example, the dispersion of Example 27 replaces about 20% of the phenol used during the synthesis of a phenol-formaldehyde resin. In preparing the adhesive, the procedure of Example 13 was followed where the lignin dispersion of Example 27 was used instead of the organosolv lignin. The final resin composition was about 54% solids of which about 12% was organosolv lignin. The final adhesive viscosity was about 174 cps (measured at 25°C).

EXAMPLE 31

The phenol-formaldehyde resin of Example 30 was tested as a face resin on boards manufactured according to the manufacturing conditions shown in Table 5. The results in Table 25 demonstrates that the boards have good properties.

EXAMPLE 32

In this example, alkaline ALCELL^® lignin solution was prepared by addition of sodium hydroxide and

ALCELL^® lignin to water. About 1200 grams of a lignin cake containing about 65% solids were mixed with about 270 grams of an about 50% sodium hydroxide solution and about 559 grams of water to obtain a solution containing about 44.9% solids and having a viscosity of about 1300 cps The solution composition was adjusted by addition of water to contain about 40% solids and to a viscosity of about 227 cps (measured at 25°C).

EXAMPLE 33

The alkaline ALCELL^® lignin solution of Example 32 can be used as a partial replacement for phenol during phenol-formaldehyde resin synthesis. In preparing the resin, the procedure of Example 13 was followed and the alkaline organosolv lignin solution of Example 32 replaces the organosolv lignin used. The final adhesive composition was about 54% total solids of which about 12% was organosolv lignin. The final adhesive viscosity was about 204 cps (measured at 25°C) .

EXAMPLE 34

The phenol-formaldehyde resin of Example 33 was tested as a face resin on boards manufactured following the parameters of Table 5. The results in Table 26 demonstrate that the boards have good properties and were competitive with control boards.

EXAMPLE 35

In this example, the alkaline lignin solution of

Example 32 was added to the phenol-formaldehyde resin of Example 17 and used in plywood applications. In this example, about 568.7 grams of Example 17 phenol- formaldehyde resin was blended with 128.5 grams of the alkaline lignin solution of Example 32. The final adhesive was about 42.4% total solids of which about 15% was organosolv lignin. The final adhesive a viscosity was about 685 cps (measured at 25°C).

EXAMPLE 36

The adhesive of Example 35 was tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. In this example, the panels were pressed for about 6 minutes, at a press temperature of about 300°F and a pressure of about 200 psi. The panels were tested using the vacuum pressure and four-hour alternate boil test under conditions that promote over- penetration. The adhesive was compared to a commercial phenol-formaldehyde resin. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 27 indicate that the adhesive of Example 35 was performing equal to or better than the commercial adhesive.

EXAMPLE 37

The adhesive of Example 35 was tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. In this example, the panels were pressed for about 5 minutes, at a press temperature of about 300°F, and a pressure of about 200 psi. The panels were tested using the vacuum pressure and four-hour alternate boil test under conditions that promote dry-out. The adhesive was compared to a commercial phenol- formaldehyde resin. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 28 indicate that the adhesive of Example 35 was performing equal to or better than the commercial adhesive.

EXAMPLE 38

The adhesive of Example 35 was tested by the preparation of 5/8" three ply panels made with 1/8" Douglas Fir veneer. In this example, standard production methods were simulated by using about 6.5 minutes prepress time, about one minute closed assembly time, about 0.5 minutes fry time at an assembly time ranging from about 5 to 45 minutes. The panels were pressed for about 6.5 minutes, at a press temperature of about 300°F and at a pressure of about 200 psi. The panels were tested under normal conditions. The adhesive was compared to a commercial phenol-formaldehyde resin. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive. The results in Table 29 indicate that the adhesive of Example 35 was performing equal to or better than the commercial adhesive.

EXAMPLE 39

In this example, ALCELL^® lignin was phenolated prior to phenol-formaldehyde resin synthesis for waferboard and oriented strandboard applications. About 0.67 moles phenol, about 0.14 moles sodium hydroxide and about 20% organosolv lignin on phenol weight basis were reacted for about 60 minutes and at a temperature of about 180°C. The reaction mixture was cooled to about 45°C, and about 0.33 moles phenol, about 4.1 moles formaldehyde and about 0.24 moles sodium hydroxide were added. Enough water was added such that the final adhesive has a total resin solids content of about 55%. The mixture was heated to 80°C and polymerization was continued until a target viscosity of from about 200 to 400 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to constitute 5% of the resin liquid weight and the resin was quickly cooled to 25°C or below. The final adhesive composition was about 55% resin solids of which about 12% was organosolv lignin. The final adhesive viscosity was about 205 cps (measured at 25°C) .

EXAMPLE 40

The adhesive of Example 39 was tested by the preparation of three layers waferboard panels. The manufacturing conditions of Table 5 were followed. The results of board testing were shown in Table 30 and demonstrate that the boards prepared were competitive with control boards.

EXAMPLE 41

In this example, ALCELL^® lignin was phenolated prior-. to phenol-formaldehyde resin synthesis used in plywood applications. In this example, about 15% of the total phenol used in the resin was replaced by organosolv lignin such as ALCELL^® lignin. About 0.28 moles of phenol and about 0.06 moles sodium hydroxide were reacted for about 60 minutes and at a temperature of about 180°C. The mixture was cooled to about 45° and about 0.72 moles phenol, about 2.69 moles formaldehyde and water was added in an amount sufficient such that the final resin solids were about 42% solids. About 0.12 moles of sodium hydroxide were added and the mixture was refluxed for about 20 minutes. The mixture was then cooled to about 80°C and the polymerization continued until a viscosity of about 2500 cps (measured at 25°C) was reached. The mixture was then cooled to about 70°C and about 0.24 moles sodium hydroxide was added. The polymerization was continued until a viscosity of about 2500 cps (measured at 25°C) was reached. The mixture was cooled to about 65°C and about 0.18 moles sodium hydroxide were added. The polymerization was continued until a viscosity of from about 1500 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to constitute about 5% of the resin weight and the resin was cooled to 25°C or below. The final adhesive composition was about 42% total solids of which about 8% was organosolv lignin.

EXAMPLE 42

An adhesive for plywood manufacture was prepared using the procedure of Example 19. In this particular example, about 7.11% by weight of Example 41 phenol- formaldehyde resin, about 21.35% by weight water, about 12.09% by weight of a mixture of additives (e.g. fillers or viscosity modifiers) and about 2.49% by weight alkali, preferably sodium_hydroxide, were mixed for from about 5 to 15 minutes. The balance of Example 41 resin, about 56.93% by weight was added to the mixture. The final adhesive composition was from about 24 to 32% total solids of which about 1 to 7% was organosolv lignin. The final adhesive viscosity was about 5600 cps (measured at 25°C).

EXAMPLE 43

The adhesives in Table 31 with varying levels of ALCELL^® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. The panels were pressed using a press temperature of about 300°F and a pressure of about 200 psi. To accentuate over-penetration, a wet glue spread of about 70 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of from about 2 to 3 minutes and a pressing time of about 6 minutes. The press was closed immediately after loading so that there was no "fry-time". The panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 31. A high-percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.

EXAMPLE 44

The adhesives in Table 32 with varying levels of ALCELL^® lignin substitution were tested by the preparation of 3/8" three ply panels made- with 1/8" Douglas Fir veneer. To accentuate dry-out, a wet glue spread of about

40 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of about 40 minutes and a pressing time of about 5 minutes. The press was closed immediately after loading so that there was no

"fry-time". The panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 32. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.

EXAMPLE 45

The adhesives in Table 33 with varying levels of

ALCELL^® lignin substitution were tested by the preparation of 5/8" five ply panels made with 1/8" Douglas Fir veneer.

In this example, adhesion performance was studied under simulated normal assembly conditions at slightly high and normal wet spreads. Normal production methods were simulated by using 5 minutes prepress conditions, one minute closed assembly time and 0.5 minute fry time at different assembly times ranging from about 5 to 30 minutes. The press temperature was set at about 300°F, and a pressure of about 200 psi. The wet glue spread was about 60 lbs of adhesive per 1,000 square feet of double glue line. The panels were tested using the vacuum pres- sure and four-hour alternate boil test and the results were summarized in Table 33. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.

EXAMPLE 46

In this example, low molecular weight ALCELL® lignin was used as a partial replacement for phenol in the manufacture^, of phenol-formaldehyde resins for waferboard and oriented strandboard application. To the adhesive, the procedure of Example 13 was used and the low molecular weight ALCELL^® lignin replaces the organosolv lignin. The final adhesive composition was about 54% total solids of which about 12% was organosolv lignin. The final adhesive viscosity was about 204 cps (measured at 25°C) .

EXAMPLE 47

The adhesive of Example 46 was tested by the preparation of three layers waferboard panels. The manufacturing conditions of Table 5 were followed. The results of board testing are shown in Table 34 and demonstrate that the boards prepared were competitive with control boards. EXAMPLE 48

In this example, ALCELL^® lignin substituted for about 20% of the phenol on a phenol weight basis used in phenol-formaldehyde resin manufacture. About 1.3 moles of formaldehyde, 0.06 moles of sodium hydroxide and about 20% ALCELL^® lignin on a weight basis with phenol were reacted for about 90 minutes and at a temperature of about 70°C. The reaction mixture was cooled to about 30°C and about one mole of phenol, about 1.15 mole formaldehyde and about 0.27 moles of sodium hydroxide were added. The mixture was heated to about 80°C and polymerization was continued until a target viscosity of from about 200 to 700 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to react with the excess formaldehyde and the resin was quickly cooled to about 25°C or below. The final resin composition was about 57% total solids of which about 12% was organosolv lignin. The final adhesive viscosity was about 240 cps (measured as 25°C).

EXAMPLE 49

In this example, organosolv lignin such as

ALCELL^® lignin substituted for about 40% phenol on a weight basis during phenol formaldehyde resin manufacture. About 2.9 moles of formaldehyde, about 0.16 moles sodium hydroxide, about 40% organosolv lignin on a weight basis with phenol and water were reacted for about 90 minutes and at a temperature of about 70°C. The reaction mixture was cooled to about 45°C, about one mole phenol and about 0.31 moles of sodium hydroxide were added. The mixture was heated to about 80°C and polymerization was continued until a target viscosity of about 200 to 400 cps (measured at 25°C) was reached. Urea was added in an__amount equal to about 5% of total resin weight, and the resin was quickly cooled to about 25°C or below. The final resin composition was about 57% total solids of which about 25% was organosolv lignin. The resin viscosity was about 240 cps (measured at 25°C).

EXAMPLE 50

The adhesives of Examples 48 and 49 have been tested as face resins for waferboard and oriented strandboard applications. The manufacturing conditions of Table 5 were followed. The results of board testing are shown in Table 35 and demonstrate that the boards prepared were competitive with control boards.

EXAMPLE 51

In this example, ALCELL^® lignin was acid methylolated as a first step in the synthesis of a phenol- formaldehyde resin for waferboard and oriented strandboard applications. About 20% on a weight basis of the phenol used in the manufacture of the phenol-formaldehyde resin was replaced by organosolv lignin. Thus 18.8 grams of lignin were dissolved in about 0.32 moles of phenol, about 0.39 moles formaldehyde and 0.003 moles of sulfuric acid. The mixture was reacted for about 45 minutes at a temperature of about 80°C. The reaction mixture was cooled to about 45°C and about 0.006 moles sodium hydroxide was added to neutralize the sulfuric acid. About 0.68 moles of phenol, about 2.36 moles of formaldehyde and about 0.31 moles of sodium hydroxide were added. Enough water was added such that the total resin solids were about 55%. The mixture was heated to about 80°C and polymerization was continued until a target viscosity of from 200 to 400 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to constitute about 5% of the resins liquid weight and the resin was quickly cooled to about 25°C or below. The final adhesive composition was about 55% total solids of which about 12% was organosolv lignin.

EXAMPLE 52

The adhesive of Example 51 was tested as a face resin in waferboard applications. Results in Table 36 demonstrate that the boards prepared were competitive with control boards.

EXAMPLE 53

In this example, ALCELL^® lignin was acid methylolated as a first step in the synthesis of a phenol- formaldehyde resin for plywood applications. About 15% on a weight basis of the phenol used in the manufacture of the phenol-formaldehyde resin was replaced by ALCELL® lignin. About 14.1 grams of organosolv lignin, about 0.23 moles phenol, about 0.31 moles formaldehyde and about 0.002 moles sulfuric acid were reacted for about 45 minutes at a temperature of about 80°C. The mixture was cooled to a temperature of about 35°C and about 0.012 moles sodium hydroxide was added to neutralize the sulfuric acid. Enough water was added such that the final resin solids were about 42%. About 0.77 moles phenol and about 2.84 moles formaldehyde were added. About 0.18 moles of sodium hydroxide were added. The mixture was heated to reflux for about 15 minutes-then cooled to about 80°C. The polymerization was continued until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. The mixture was cooled to about 70°C. About 0.24 moles of sodium hydroxide were added and the polymerization continued until a viscosity of from about 2000 to 2500 cps (measured at 25°C) was reached. The mixture was cooled to about 65°C. About 0.18 moles sodium hydroxide were added and the polymerization continued until a viscosity of about 1500 to 1800 cps (measured at 25°C) was reached. Urea was added in an amount sufficient to constitute about 5% of the final adhesive weight and the resin was cooled to 25°C or below. The final resin composition was about 42% total solids of which about 8% was organosolv lignin.

EXAMPLE 54

An adhesive for plywood manufacture was prepared using the procedure of Example 19. In this particular example, about 7.11% by weight of Example 52 phenol- formaldehyde resin, about 21.35% by weight water, about 12.09% by weight of a mixture of additives (e.g. fillers or viscosity modifiers) and about 2.49% by weight alkali, preferably sodium hydroxide, were mixed for from about 5 to 15 minutes. The balance of Example 52 resin, about 56.93% by weight was added to the mixture. The final adhesive composition was from about 24 to 32% total solids of which about 1 to 7% was organosolv lignin. The final adhesive viscosity was about 5600 cps (measured at 25°C) .

EXAMPLE 55

The adhesives in Table 37 with varying levels of ALCELL^® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. The panels were pressed using a press temperature of about 300°F and a pressure of about 200 psi. To accentuate over-penetration, a wet glue spread of about 70 lbs of adhesive per 1,000 square feet of double glue line was used with an assembly time of from about 2 to 3 minutes and a pressing time of about 6 minutes. The press was closed immediately after loading so that there was no "fry-time". The panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 37. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.

EXAMPLE 56

The adhesives in Table 38 with varying levels of ALCELL^® lignin substitution were tested by the preparation of 3/8" three ply panels made with 1/8" Douglas Fir veneer. To accentuate dry-out, a wet glue spread of about

"fry-time". The panels were tested using the vacuum pressure and four-hour alternate boil test and the results are summarized in Table 38. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.

EXAMPLE 57

The adhesives in Table 39 with varying levels of ALCELL^® lignin substitution were tested by the preparation of 5/8" five ply panels made with 1/8" Douglas Fir veneer. In this example, adhesion performance was studied under simulated normal assembly conditions at slightly high and normal wet spreads. Normal production methods were simulated by using 5 minutes prepress conditions, one minute closed assembly time and 0.5 minute fry time at different assembly times ranging from about 5 to 30 minutes. The press temperature was set at about 300°F, and a pressure of about 200 psi. The wet glue spread was about 60 lbs of adhesive per 1,000 square feet of double glue line. The panels were tested using the vacuum pres- sure and four-hour alternate boil test and the results were summarized in Table 39. A high percent (%) wood failure indicates that the adhesive was holding and that the wood was breaking rather than the adhesive.

EXAMPLE 58

In this example, a lignin dispersion was prepared as in Example 27 using 0.5% monoethanolamine as dispersant. The lignin dispersion contained about 52% total solids and was blended with Example 48 resin containing 57% solids. The resulting mixture contained about 56% total solids of which 30% was organosolv lignin. The resulting mixture was tested as face resin for waferboard applications and the manufacturing conditions of Table 5 with a press time of 290 seconds. The results of board testing are shown in Table 40 and demonstrate that the boards prepared were competitive with control.

EXAMPLE 59

In this example, an ALCELL lignin dispersion was prepared and was blended with a core phenol-formaldehyde resin to form the adhesive. In preparing the lignin dispersion, about 4.25% ammonium hydroxide based on lignin weight was added to water and then ALCELL^® lignin was added slowly with agitation to form a stable dispersion that contained about 52% total solids. About 44 grams of this dispersion was mixed with 187 grams of a phenol- formaldehyde resin (e.g. core resin GP119C24). The final adhesive composition was adjusted by addition of water and sodium hydroxide to about 50% solids and pH 12.6. The final adhesive had a viscosity of about 260 cps (measured at 25°C) with 20% lignin based on phenolic solids in the adhesive.

EXAMPLE 60

The adhesive of Example 59 was tested by preparing boards manufactured according to the parameters of Table 5 except that the press time was 290 seconds. The results of board testing are shown in Table 41 and demonstrate that the boards prepared were competitive with the control boards.

Example 61

About 1017 grams of Southern Pine particleboard furnish was_ blended with wax of about 1.7% wax solids on oven dried furnish and ALCELL^® lignin of about 10% lignin solids on furnish. This blend was pressed at 360°F platten temperature for 7 minutes using a maximum pressure of about .580 psi to form a 3/8" panel. . decompression time of 30 seconds was used. After removing the panels from the press they were placed in an enclosed chamber to simulate the hot stacking that normally occurs under industrial manufacturing conditions.

Example 62

In this example, low molecular weight ALCELL® lignin is methylolated by addition of about 54 gms moles of formaldehyde to a solution composed of 210 gms water, 210 gms low molecular weight ALCELL^® lignin and one mole of sodium hydroxide. The mixture is reacted at about 70°C for about 90 minutes. About 0.6 moles urea is added and the reaction is quickly cooled to about 25°C or below.

Example 63

About 2034 grams of Southern Pine particle board furnish at about 8% moisture content was blended with wax at about 0.6% wax solids on furnish and methylolated low molecular weight lignin solution from Example 62 at about 6.8% solids on furnish. The blend was pressed into 3/4" particleboard panels at 360°F platten temperature for 11 minutes using a maximum pressure of about 580 psi. A decompression time of 30 seconds was used. After removing the panels from the press they were placed in an enclosed chamber to simulate the hot stacking that normally occurs under industrial manufacturing conditions.

Example 64

This example illustrates the manufacture of wallboard useful as a substitute for gypsum board. Shredded newspaper or polyethylene coated paper (^" 2,000 grams) was sprayed with Paracol wax 2370 (3.7% wax solids by weight on paper) and then ALCELL^® lignin (10% by weight on paper) was blended in. The resulting blend of paper, organosolv lignin and wax was positioned between two paper facings, similar to those used in the manufacture of^" convention gypsum board. Before positioning the blend, 47 grams of a wax and organosolv lignin blend comprising 29 parts of organosolv lignin, 60 parts of wax solids and 60 parts of water is applied on the interior of the paper that is facing in contact with the blend. The resulting panel was pressed into a 3/8" board at from about 320 to about 330°F for from about 7 to about 9 minutes and using a maximum pressure of about 570 psig. A decompression time of about 30 seconds was used. The panels from the press were removed and placed in an enclosed chamber to simulate the hot stacking that occurs in industrial operation. As shown in Table 42, the boards made with recycled paper and organosolv lignin as the adhesive have superior strength, when compared with conventional gypsum boards.

Example 65

Molded products of various shapes, such as one- piece pallets, pallet components, doors, door facings, trim moldings, interior paneling for automobiles, one- piece packaging containers degradable plant pots, can also be manufactured from waste paper and lignin. About 1900 grams of shredded paper (newspaper, polyethylene coated paperboard, publication grade coated) was blended with Paracol 2370 wax at about 3.9% wax solids by weight and ALCELL^® lignin at about 10.5% by weight. The resulting blend was pressed between two forming plates for about 9 minutes, at about 330°F and about 570 psi followed with decompression for about 30 seconds. A molded product was obtained with about 3/8" thickness which approximates the shape of a miniature one-piece pallet.

Example 66

In this example the advantages of using wax coated paperboard as fiber in combination with other types of fibers are illustrated. It should be mentioned that this type of paper is currently impossible to recycle for paper making given its high wax content, typically of about 50%. About 1900 grams of shredded wax coated paperboard by itself or in combinations with publication grade coated paper were sprayed with about 5% water, blended with about 10% ALCELL^® lignin and pressed as described in Example 65. As shown in Table 43 the use of increasing levels of wax coated paperboard results in a progressive improvement in water resistance.

TABLE 1

Wafer

Type commercial aspen

Moisture Content (%) 4.6

Additives

Binder Content (% by wafer weight) 2.5 Wax Content (% solids by wafer weight) 1.0

Press Conditions

Temperature (°F) 410 Time (seconds) 180 Pressure (psi) 540

Board

Thickness (inches) 3/8+20/

1000

Density (Ib./cu.ft.) 39.8-43.0

No. Panels/Condition 3

Panel Dimensions 15" x 15"

TABLE 2

Wafer

Type commercial aspen

Moisture Content (%) 4.6

Additives

Binder Content (% by wafer weight) 4.5 Wax Content (% solids by wafer weight) 1.0

Press Conditions

Temperature (°F) 410 Time (seconds) 300

Pressure (psi) 540

Board

Thickness (inches) 3/8+20/1000

Density (lb./cu.ft.) 39.8-43.0 No. Panels/Condition 3-4

Panel Dimensions 15" x 15"

TABLE 3

Wafer

Type commercial aspen Moisture Content (%) 4.6

Additives

Binder Content (% by wafer weight) 1.95 Wax Content (% solids by wafer weight) 1.0

Press Conditions

Temperature (°F) 400 Time (seconds) 170 Pressure (psi) 550-750

Board

Thickness (inches) 7/16+20/1000 Density (lb./cu.ft.) 38.0-42.0 No. Panels/Condition 4-5 Panel Dimensions 42" x 42"

TABLE 4

Wafer

Type commercial aspen

Moisture Content (%) 4.6

Additives

Binder Content (% by wafer weight) 1.95 Wax Content (% solids by wafer weight) 1

Press Conditions

Temperature (°F) 400 Time (seconds) 180 Pressure (psi) 540

Board

Thickness (inches) 7/16+20/1000 Density (lb./cu.ft.) 38.0-42.0 Panels/Condition 3 Panel Dimensions 15" X 15"

Additives

Wax Content (% solids by wafer weight) 0.9

Press Conditions

Temperature (°F) 400 Time (seconds) 255 Pressure (psi) 540

Board

Thickness (inches) 7/16+20/1000 Density (lb./cu.ft.) 38.0-42.0 No. Panels/Condition 3 Panel Dimensions 15" x 15"

Organosolv

•__

Lignosulfonate*

Kraft³

Note: Figures in parenthesis are in percent (%) and based on values for board made with a 100% phenol- formaldehyde resin. Key:

MORE = Modulus of Rupture (psi) MOE = Modulus of Elasticity (Kpsi) IB = Internal Bonding (psi) D-4 = Single Cycle Bending American Plywood Association Test Method (lbs)

Standards of Measurement

MORE, MOE, IB: ASTM Standard D 1037-78 D-4, D-5: Cycle Bending American Plywood Association Test Method (1) ALCELL^® Lignin, Repap Technologies, Valley

Forge, PA

(2) Orzan S by ITT Rayonier, Stamford, CT

(3) Indulin AT by Westvaco, New York, NY

MOR psi ( % )

100% GP5415¹ 3456

(100 )

80% GP5415 3654 20% ALCELL^® (106)

Lignin

Conditions: 4005F Temperature, 170 seconds

100% BD909 used in Core Layer

D-5 = Six Cycle Bending American Plywood Association Test Methods (lbs)

(1) Face resin manufactured by Georgia Pacific

(Crossett, Arkansas)

TABLE 8

MOR D-4 IB psi lbs psi (%) (%) (%)

100% GP-5415 used in face layer, Georgia Pacific, Crossett, Arkansas

(1) Core resin by Reichhold, Bellevue, Ontario, Canada.

IB psi

(%)

2% Phenol

100% BD802

80% BD802

20% ALCELL^® Lignin

80% BD802

18% ALCELL^® Lignin

2% Phenol

Conditions:

BD023 and BD802 are both manufactured by Reichhold Ltd, Bellevue, Ontario, Canada.

GP5415 is manufactured by Georgia Pacific, Crossett, Arkansas.

100% BD909

80% BD909

20% ALCELL^® Lignin

80% BD909 16% ALCELL^® Lignin

4% Low Molecular Weight ALCELL^® Lignin

(1) Resin manufactured by Reichhold Ltd, Bellevue, Ontario, Canada

80% BD909 3636 110 45

18% ALCELL^® Lignin (85) (85) (68) 2% 2,4-Dimethyl Phenol

80% BD909 3876 154 50

18% ALCELL^® Lignin (91) (109) (76) 2% 2,4,6-Trimethyl Phenol

Conditions:

100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas.

Key:

(1) Core resin manufactured by Reichhold Ltd, Bellevue, Ontario, Canada

100% GP5478² 4042 157 59

(100) (100) (100)

80% GP5478

20% ALCELL^® Lignin

Conditions:

100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas.

Key.:

(1) Core resin manufactured by Reichhold Ltd, Bellevue, Ontario, Canada

(2) Core resin manufactured by Georgia Pacific, Crossett, Arkansas

TABLE 13

MOR D-4 IB psi lbs psi (%) (%) (%)

100% GP5479- 4042 157 59 (100) (100) (100)

80% GP5479 4243 176 56

19.2% ALCELL^® Lignin (103) (112) (96) 0.8% PTBP

100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas.

Key.:

( 1 ) Core resin manufactured by Georgia Pacific , Crossett , Arkansas .

100% BD909 170 4009 58 194 177 (100) (100) (100) (100)

80% BD909 170 3503 52 159 149

20% ALCELL Lignin (87) (90) (82) (84)

80% BD909 200 4048 64 218 198 20% ALCELL Lignin (100) (110) (112) (112)

80% BD909 230 4679 72 238 220

20% ALCELL Lignin (117) (124) (123) (124)

Conditions:

400°F temperature 100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas.

100% BD909

80% BD909 20% ALCELL^®

Lignin

80% BD909 415 20% ALCELL^®

Lignin

Conditions:

100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas.

100% BD909 4310 81 225

(100) (100) (100)

80% BD909 3894 71 177

20% ALCELL^® Lignin (90) (88) (79)

80% BD909 4681 74 230 20% Baked ALCELL^® Lignin (109) (91) (102) 160°C - 60 min.

Conditions:

100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas.

100% BD909 4310 81 225 (100) (100) (100)

80% BD909 138 3891 69 184 20% ALCELL^® (90) (85) (82) Lignin

80% BD909 157 3748 77 210 20% ALCELL^® (87) (95) (93) Lignin

80% BD909 192 3963 70 216 20% ALCELL^® (92) (86) (96) Lignin

80% BD909 235 4447 86 240 20% ALCELL^® (103) (106) (107) Lignin

Conditions:

100% GP5415 in face layer manufactured by Georgia Pacific, Crossett, Arkansas. 4.5% Example 12 Resin

3.6% Example 12 Resin 5159 103 284 0.9% ALCELL^® Lignin (100) (89) (102)

Example 12 Resin 5138 116 279 (100) (100) (100)

Example 13 Resin 5279 109 274 700 cps Viscosity (103) (94) (98)

Example 13 Resin 4604 115 243 390 cps Viscosity (90) (99) (87)

TABLE 20

Vacuum-Pressure 4 Hour- Alt Boil

Commercial Adhesive Example 19 Adhesive

(1) Adhesive prepared from Canadian Reichold Chemical Company BB-055 resin as in Example 19

4 Hour- Alt Boil

Commercial Adhesive Example 20 Adhesive Example 21 Adhesive

(1) Borden 3130-H Adhesive

(2) Borden 3130-H Adhesive containing about 4.7% organosolv lignin

TABLE 22

Vacuum-Pressure 4 Hour- Alt Boil (%) (%)

Press Time: 6 min

Example 20 Adhesive Commercial Adhesive^ 40 40

Press Time: 5 min

Example 20 Adhesive 62 88 Commercial Adhesive¹ 7 15

Press Time: 4.5 min

Example 20 Adhesive Commercial Adhesive¹

(1) Borden 313OH Adhesive

TABLE 23

Vacuum-Pressure 4 Hour- Alt Boil Panels¹ (%) (%)

3 ply, 5/16" 93.2 94.7 5 ply, 21/32" 89.1 94.6 5 ply, 25/32" 93.4 93.8

(1) Douglas Fir veneer

100% PH-102¹ 5204 276 83 (100) (100) (100)

Conditions:

100% SL-101 used in Core layer manufactured Dyno Polymers, Virginia, Minnesota.

Key;

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota

100% PH-102¹ 5204

(100)

Ammonia Dispersion 5176 20% Phenol Replacement (119)

Conditions:

100% SL-101 used in core layer manufactured by Dyno Polymers, Virginia.

Key:

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota.

100% PH-102¹ 5204 276 83

(100) (100) (100)

ALCELL^® lignin as 4679 310 84 20% Phenol Replacement (90) (112) (101)

Conditions:

100% SL-101 used in Core Layer manufactured by Dyno Polymers, Virginia, Minnesota.

Key:

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota.

TABLE 27

Vacuum-Pressure Over-penetration (%)

85% Example 17 Resin 68 15% Alkaline ALCELL^® Lignin Solution

100% Commercial Adhesive 50

Conditions:

(1) The wet glue spread is about 70 lbs of adhesive per 1,000 square feet of double glue line. (2) The assembly time is about 2.5 minutes.

TABLE 28

4 Hour- Alt Boil Dry-out Test

(%)

85% Example 17 Resin 78.6 15% Alkaline ALCELL^® Lignin Solution

100% Commercial Adhesive 72

Conditions:

(1) The wet glue spread is about 40 lbs of adhesive per 1,000 square feet of double glue line. (2) The assembly time is about 40 minutes.

TABLE 29

Vacuum-Pressure 4 Hr- Alt Boil Knife

(%) (%) (%)

85% Example 17 Resin 78 72 96 15% Alkaline ALCELL^® Lignin Solution

100% Commercial Resin 74 70 97

Conditions:

(1) The wet glue spread is about 65 lbs of adhesive per 1,000 square feet of double glue line.

(2) The assembly time is about 5 to 45 minutes.

(3) The prepress time is about 6 minutes.

(4) The closed assembly time is about one minute.

IB psi

(%)

100% PH-102¹ 4006 182 63

(100) (100) (100)

20% Phenol Replacement 4413 278 62

(110) (131) (98)

Conditions: 100% GP92C60 in core layer manufactured by Georgia Pacific, Crossett, Arkansas.

Key:

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota.

TABLE 31

Vacuum-Pressure Knife (%) (%)

Example 42 Adhesive 42 91 2.5% ALCELL^® Lignin

Example 42 Adhesive 51 67 8.5% ALCELL^® Lignin

Example 42 Adhesive 72 93 2.2% ALCELL^® Lignin

TABLE 32

4 Hr- Alt Boil Knife (%) (%)

Example 42 Adhesive 78 81 2.5% ALCELL^® Lignin

Example 42 Adhesive 59 77 4.9% ALCELL^® Lignin

Example 42 Adhesive 57 90 4.1% ALCELL^® Lignin

TABLE 33

Vacuum-Pressure 4 Hr- Alt Boil Knife (%) (%) (%)

Example 42 Adhesive 74 72 90 2.5% ALCELL^® Lignin

Example 42 Adhesive 66 62 88

4.9% ALCELL^® Lignin

Example 42 Adhesive 80 72 93

4.1% ALCELL^® Lignin

TABLE 34

MOR psi (%)

100% PH-102¹ 4006

(100)

20% Phenol Replacement 4258 by Low Molecular Weight (106)

ALCELL^® Lignin

Conditions:

Key:

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota.

0% Phenol Replacement 5015 205 76

(100) (100) (100)

20% Phenol Replacement 4593 204 76

(92) (100) (100)

30% Phenol Replacement 4169 (83)

40% Phenol Replacement 4522

(90)

Conditions:

100% GP92C60 in core layer manufactured by Georgia Pacific, Crossett, Arkansas.

Key:

(1) 100% PH-102 face resin manufactured by Dyno Polymers, Virginia, Minnesota.

100% PH-102¹ 4242 195 66

0% Phenol Replacement (100) (100) (100)

20% Phenol Replacement 4274 268 72

(101) (137) (109)

Conditions:

100% SL-101 in core layer manufactured by Dyno Polymers, Virginia, Minnesota.

Key.;

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota

Knife ( )

Example 20 Adhesive

89 4.2% ALCELL^® Lignin

Example 20 Adhesive 26.6 85 8.5% ALCELL^® Lignin

Example 19 Adhesive 39.7 81 2.2% ALCELL^® Lignin

Example 19 Adhesive 21.7 74 4.4% ALCELL^® Lignin

Example 54 Adhesive 42.9 78 2.2% ALCELL^® Lignin

Example 54 Adhesive 31.8 69 4.4% ALCELL^® Lignin

TABLE 38

4 Hr- Alt Boil Knife (%) (%)

Example 20 Adhesive 70 74 4.2% ALCELL^® Lignin

Example 20 Adhesive 78. 1 85 8.5% ALCELL^® Lignin

Example 19 Adhesive 47 . 4 79 2. 2% ALCELL^® Lignin

Example 19 Adhesive 43 .7 77 4.4% ALCELL^® Lignin

Example 54 Adhesive 35.3 70 2.2% ALCELL^® Lignin

Example 54 Adhesive 28.4 69 4.4% ALCELL^® Lignin

TABLE 39

Vacuum-Pressure 4 Hr- Alt Boil Knife (%) (%) (%)

Example 20 Adhesive 57 60.2 81 4.2% ALCELL^® Lignin

Example 20 Adhesive 86.4 86 96

8.5% ALCELL^® Lignin

Example 19 Adhesive 48 41.8 68

2.2% ALCELL^® Lignin

Example 19 Adhesive 48 62.5 68

4.4% ALCELL^® Lignin

Example 54 Adhesive 38.3 29.5 64

2.2% ALCELL^® Lignin

Example 54 Adhesive 44 48.8 69 4.4% ALCELL^® Lignin

TABLE 40

100% PH-102,

20% Ex. 58 Dispersion 80% Ex. 48 Resin

Conditions:

Resin GP119C24 used in core layer manufactured by Georgia Pacific, Crossett, Arkansas.

Key:

(1) Face resin manufactured by Dyno Polymers, Virginia, Minnesota

Conditions:

100% PH-102 used in face layer manufactured by Dyno Polymers, Virginia.

Key:

(1) GP119C24 resin manufactured by Georgia Pacific, Crossett, Arkansas

TABLE 42

A B C D E

Gypsum 29.75 39.8 18.35 55 2.3

Newspaper 82.1 137.55 36.4 9.08 2.0

Coated 59.3 108.8 35.25 8.81 2.4 Polyethylene

Key

A: Flex Strength (lbs)

B_: Edge Hardness (gms)

C: Nail Push (lbs); 0.078" pilot hole drilled in sample prior to inserting 0.100" diameter nail

D: % Weight Gain after Soaking; Soak test done for 2 hours at room temperature in deionized water

E: % Thick Swell after Soaking; Soak test done for 2 hours at room temperature in deionized water

TABLE 43

% Weight Gain

Fiber Source After Soaking

100% wax coated 12.0 paperboard

75% wax coated paperboard

25% publication 18.2 paperboard

10 50% wax coated paperboard 50% publication 20.6 coated paper

The invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various modifications and changes can be made without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the specific materials, procedures and examples hereinbefore described being merely preferred embodiments.

For example, the dry organosolv lignin could be mixed into a low viscosity liquid phenolic resin for use in waferboard manufacture and alternatively, the organosolv lignin could be formulated as a component of a wax emulsion by mixing with small amounts of a dispersing agent. In another example, the performance of the plywood adhesive could also be improved by the addition of a modifier.

In another example, at the commercial level, the organosolv lignin and the phenolic resin could be applied simultaneously by independent application means. The lignin can be applied in liquid, slurry or powder form.

In another example, the lignin in either liquid, slurry or powder form could be added to the liquid precursor of a , powder phenol-formaldehyde resin and the mixture spray-dried and used to obtain a lignin/phenol formaldehyde resin blend.

In another example, it could be possible to chemically modify an organosolv lignin and use it in adhesive applications without blending with a phenol- formaldehyde resin.- Yet in another example, lignin and lignin-based wood adhesives can have applications to the manufacture of molded products using newspapers, coated papers, wax coated paperboard as a source of cellulosic fibers with significant environmental benefits.

Additionally, it could be possible to utilize the invention to make lignins other than organosolv lignin compatible with phenol formaldehyde resins and the invention could be used in structural and nonstructural wood products applications other than for plywood, waferboard, particleboard and wallboard substitutes.

Claims

We claim:

. 1. An adhesive for wood composite comprising an organosolv lignin and a phenol-formaldehyde resin in a weight ratio of from about 0.5:99.5 to about 70:30 based on phenolic solids in said phenol-formaldehyde resin.

2. The adhesive of Claim 1 wherein said wood composite is selected from the group consisting of waferboard, oriented strandboard, particleboard, plywood, wallboard and molded products.

3. The adhesive of Claim 2 wherein said phenol- formaldehyde resin is a powder resin.

4. The adhesive of Claim 3 wherein said organosolv lignin is blended with said phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 70:30 based on phenolic solids in said phenol-formaldehyde resin.

5. The adhesive of Claim 4 wherein said organosolv lignin is baked prior to blending with said phenol-formaldehyde resin for improving the performance of said phenol-formaldehyde resin and said organosolv lignin.

6. The adhesive of Claim 4 wherein said organosolv lignin is flash dried prior to blending with said phenol-formaldehyde resin for improving the performance of said phenol-formaldehyde resin and said organosolv lignin.

7. The adhesive of Claim 4 which further comprises a modifier for improving the performance of said phenol-formaldehyde resin and said organosolv lignin.

8. The adhesive of Claim 7 wherein said modifier and said organosolv lignin together substitute for from about 5% to about 75% based on phenolic solids in said phenol-formaldehyde resin.

9. The adhesive of Claim 8 wherein said modifier is selected from the group consisting of low molecular weight organosolv lignin, low molecular weight phenolic compounds, tris-(p-hydroxyphenyl) ethane, p-tert-butyl- phenol, bisphenol-A, p-cresol, p-ethylphenol, p-sec- butylphenol, p-amylphenol, p-nonylphenol, p-dodecylphenol, 2,4-dimethylphenol, 2,4,6,-trimethylphenol, para-alkyl phenols with side chains of 18 to 24 and 24 to 28 carbons, polyhydroxystyrene, creosote blends and furfural.

10. The adhesive of Claim 9 wherein said modifier is selected from the group consisting of phenol, p-tert-butylphenol, bisphenol-A and furfural.

11. The adhesive of Claim 10 wherein the weight ratio of said modifier to said organosolv lignin is from about 0.5:99.5 to 20:80.

12. The adhesive of Claim 9 wherein said modifier is a low molecular weight organosolv lignin.

13. The adhesive of Claim 12 wherein the weight ratio of said low molecular weight organosolv lignin to said organosolv lignin is from about 5:95 to 70:30.

14. The adhesive of Claim 13 wherein said low molecular weight organosolv lignin is a lignin with a molecular weight of less than about 500 g/mol, a glass transition temperature of from about 24° to 80°C and a syringaldehyde to vanillin molar ratio of from about 2.7:1 to about 5.3:1.

15. The adhesive of Claim 2 wherein said phenol- formaldehyde resin is a liquid resin.

16. The adhesive of Claim 15 wherein said organosolv lignin comprises low molecular weight organosolv lignin.

17. The adhesive of Claim 16 wherein said organosolv lignin is added to said phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of said organosolv lignin and phenolic solids in said phenol-formaldehyde resin.

18. .The adhesive of Claim 17 wherein said adhesive is prepared by condensing formaldehyde and phenol in a molar ratio of from about 2 to about 3 under alkaline conditions.

19. The adhesive of Claim 18 wherein said alkali is from about 0.12 to about 0.47 per mole of said phenol.

20. The adhesive of Claim 19 wherein said organosolv lignin is added during the preparation of said phenol-formaldehyde resin in a weight ratio of from about 0.5:99.5 to 40:60 based on phenolic solids in said adhesive.

21. - The adhesive of Claim 20 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 4.5 under alkaline conditions and reacting said organosolv lignin with said formaldehyde and said phenol during said condensation.

22. The adhesive of Claim 21 wherein said organosolv lignin is from about 1 to about 70% on a weight basis with said phenol.

23. The adhesive of Claim 22 wherein said alkali is from about 0.1 to 0.8 per mole of said phenol.

24. The adhesive of Claim 16 wherein said organosolv lignin is added to said phenol-formaldehyde resin in a weight ratio of from about 2:80 to about 30:70 based on the weight of said organosolv lignin and phenolic solids in said phenol-formaldehyde resin.

25. The adhesive of Claim 24 wherein said adhesive is prepared by condensing formaldehyde and phenol in a molar ratio of from about 2.3 to about 3 under alkaline conditions.

26. The adhesive of Claim 25 wherein said alkali is from about 0.5 to about 0.8 per mole of said phenol.

27. The adhesive of Claim 16 wherein said organosolv lignin is added during the preparation of said phenol-formaldehyde resin in a weight ratio of from about 0.8:99.2 to 35:65 based on phenolic solids in said adhesive.

28.- The adhesive of Claim 27 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2.4 to about 3.5 under alkaline conditions and reacting said organosolv lignin with said formaldehyde and said phenol during said condensation.

29. The adhesive of Claim 28 wherein said organosolv lignin is from about 2 to about 45% on a weight basis with said phenol.

30. The adhesive of Claim 29 wherein said alkali is from about 0.4 to 1 per mole of said phenol.

31. The adhesive of Claim 16 wherein said organosolv lignin is added during the preparation of said phenol-formaldehyde resin in a weight ratio of from about 0.5:99.5 to 40:60 based on phenolic solids in said adhesive.

32. The adhesive of Claim 31 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 4.5 under alkaline conditions and reacting said organosolv lignin with said formaldehyde and said phenol during said condensation.

33. The adhesive of Claim 32 wherein said organosolv lignin is from about 1 to about 70% on a weight basis with said phenol.

34. The adhesive of Claim 33 wherein said alkali is from about 0.1 to 0.8 per mole of said phenol.

35. - The adhesive of Claim 16 wherein said organosolv lignin is in alkaline solution.

36. The adhesive of Claim 35 wherein the ratio of said organosolv lignin to said alkali is from about 10 to about 25% on a weight basis with said organosolv lignin.

37. The adhesive of Claim 36 wherein said organosolv lignin alkaline solution is added during the preparation of said phenol-formaldehyde resin in a weight ratio of from about 5:95 to 60:40 based on the weight of said organosolv lignin and phenolic solids in said phenol- formaldehyde resin.

38. The adhesive of Claim 37 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 3 under alkaline conditions.

39. The adhesive of Claim 38 wherein said alkali is from about 0.12 to 0.47 per mole of said phenol.

40. The adhesive of Claim 36 wherein said organosolv lignin alkaline solution is added during the preparation of said phenol-formaldehyde resin in a weight ratio of from about 2:98 to 30:70 based on phenolic solids in said adhesive.

41. The adhesive of Claim 40 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2.3 to about 3 under alkaline conditions and reacting said organosolv lignin with said formaldehyde and said phenol during said condensation.

42. The adhesive of Claim 41 wherein said alkali is from about 0.5 to 0.8 per mole of said phenol.

•43. The adhesive of Claim 2 wherein said organosolv lignin is comprised in a dispersion.

44. The adhesive of Claim 43 wherein said dispersion further comprises a dispersing agent.

45. The adhesive of Claim 44 wherein said dispersing agent is selected from the group consisting of sodium polymethacrylate, ammonium polymethacrylate, sodium hydroxide, ammonium hydroxide, magnesium hydroxide, calcium hydroxide, monoethanola ine and diethanolamine.

46. The adhesive of Claim 45 wherein said dispersing agent and said organosolv lignin are in a weight ratio^~of from about 0.5:99.5 to about 2:98.

47. The adhesive of Claim 46^" wherein said dispersion is added to said phenol-formaldehyde resin in a weight ratio of from about 5:95 to about 60:40 based on the weight of said organosolv lignin and phenolic solids in said phenol-formaldehyde resin.

48.^' The adhesive of Claim 47 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 3 under alkaline conditions.

49. The adhesive of Claim 48 wherein said alkali is from about 0.12 to about 0.47 per mole of said phenol.

50. The adhesive of Claim 47 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 4.5 under alkaline conditions.

51. The adhesive of Claim 50 wherein said alkali is from about 0.10 to about 0.80 per mole of said phenol.

52. The adhesive of Claim 16 wherein said organosolv lignin is subjected to phenolation.

53. The adhesive of Claim 52 wherein said phenolation comprises the step of reacting said organosolv lignin with phenol in a weight ratio of from about 10 to about 80% based on total reaction weight and under alkaline conditions.

54. The adhesive of Claim 53 wherein said alkali is in a weight ratio of from about 1 to about 20% based on total reaction weight.

55. The adhesive of Claim 54 wherein said phenolated organosolv lignin is added during the preparation of said phenol-formaldehyde resin.

56.- The adhesive of Claim 55 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of^" from about 2 to about 4.5 under alkaline conditions and reacting said phenolated organosolv lignin with said formaldehyde and said phenol during said condensation.

57. The adhesive of Claim 56 wherein said phenolated organosolv lignin is from about 1 to about 70% on a weight basis with said phenol.

58. The adhesive of Claim 57 wherein said alkali is from about 0.1 to about 0.8 per mole of said phenol.

59. The adhesive of Claim 55 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2.4 to about 3.5 under alkaline conditions and reacting said phenolated organosolv lignin with said formaldehyde and said phenol during said condensation.

60. The adhesive of Claim 59 wherein said phenolated organosolv lignin is from about 1 to about 45% on a weight basis with said phenol.

61. The adhesive of Claim 60 wherein said alkali is from about 0.4 to about 1.

62. The adhesive of Claim 16 wherein said organosolv lignin is subjected to methylolation.

63. The adhesive of Claim 62 wherein said methylolation comprises the step of dissolving in phenol said organosolv lignin of from about 2 to about 60% based on total reaction weight.

64. The adhesive of Claim 63 which further comprises the step of adding formaldehyde of from about 5 to about 50% based on total reaction weight under acidic conditions.

65. The adhesive of Claim 64 wherein said phenol is from about 20 to about 50% based on total reaction weight.

66. The adhesive of Claim 65 wherein said acid is of from about 0.01 to about 3% based on total reaction weight.

67. The adhesive of Claim 66 wherein said methylolated organosolv lignin is added during the preparation of said phenol-formaldehyde resin.

68. The adhesive of Claim 67 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 4.5 under alkaline conditions and reacting said methylolated organosolv lignin with said formaldehyde and said phenol during said condensation.

69. The adhesive of Claim 68 wherein said methylolated organosolv lignin is from about 1 to about

70% on a weight basis with said phenol. 70. -The adhesive of Claim 69 wherein said alkali is from about 0.1 to about 0.8 per mole of said phenol.

71. The adhesive of Claim 67 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2.4 to about 3.5 under alkaline conditions and reacting said methylolated organosolv lignin with said formaldehyde and said phenol during said condensation.

72. The adhesive of Claim 71 wherein said methylolated organosolv lignin is from about 1 to about

45% on a weight basis with said phenol.

73. The adhesive of Claim 72 wherein said alkali is from about 0.4 to about 1 per mole of said phenol.

74.- The adhesive of Claim 62 wherein said methylolation comprises the step of reacting formaldehyde with said organosolv lignin in a weight ratio of from about 5:95 to about 50:50 under alkaline conditions.

75. The adhesive of Claim 74 wherein said alkali is in a weight ratio of from about 10:90 to about 40:60.

76. The adhesive of Claim 75 wherein said methylolated organosolv lignin is added during the preparation of said phenol-formaldehyde resin.

77. The adhesive of Claim 76 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2 to about 4.5 under alkaline conditions and reacting said methylolated organosolv lignin with said formaldehyde and said phenol during said condensation.

78. The adhesive of Claim 77 wherein said methylolated organosolv lignin is from about 1 to about

70% on a weight basis with said phenol.

79. The adhesive of Claim 78 wherein said alkali is from about 0.1 to about 0.8 per mole of said phenol.

80. The adhesive of Claim 79 wherein said adhesive is prepared by condensing formaldehyde and phenol in a mole ratio of from about 2.4 to about 3.5 under alkaline conditions and reacting said methylolated organosolv lignin with said formaldehyde and said phenol during said condensation.

81.- The adhesive of Claim 80 wherein said methylolated organosolv lignin is from about 1 to about 45% on a weight basis with said phenol.

82. The adhesive of Claim 81 wherein said alkali is from about 0.4 to about 1 per mole of said phenol.

83. A binder composition for cellulosic fibers in cellulosic fibers-based materials comprising an organosolv lignin in a weight ratio with said cellulosic fibers of from about 2:98 to about 20:80.

84. The binder composition of Claim 74 which further comprises wax in a weight ratio of from 2:98 to about 10:90 with said cellulosic fibers.

85.' A wood composite manufactured with the adhesive of Claim 2.

86. The wood composite of Claim 76 selected from the group consisting of waferboard, oriented strandboard, particleboard, plywood, wallboard and molded products.

87. A wood composite manufactured with the bindei composition of Claim 74.

88. A molded product manufactured with the binder composition of Claim 73.