JPH04156302A - Manufacture of thermoplastic wood-based material composition excellent in heat fluidity - Google Patents

Abstract

PURPOSE:To obtain wood-based material composition, which is excellent in heat fluidity and can be extruded, by a method wherein explosive crushing-treated wood-based material is reacted with the predetermined amount of monoepoxy compound or monoepoxy compound and polybasic acid anhydride. CONSTITUTION:The composition concerned is prepared by reacting 100 pts.wt. of explosive crushing-treated wood-based material as wood-based material component with 50-300 pts.wt. of monoepoxy compound or 50-300 pts.wt. of the sum of monoepoxy compound and polybasic acid anhydride. Concretely, method for adding monoepoxy compound to the hydroxyl group of the explosive crushing-treated wood-based material in the presence of potassium salt of aliphatic acid or method for alternately adding monoepoxy compound and polybasic acid anhydride to the hydroxyl group of the explosive crushing-treated wood-based material for esterification reaction is given as embodiment. By-produced oligomer is used as one component of said composition and not needed to be removed. Explosive crushing treatment can be performed through sudden decompression of wooden chips, wooden fibers, finely divided wooden powder or the like after the steaming in saturated steam having the pressure of 3-50kg/cm<2>. The obtained composition can be formed by ordinary forming method such as extrusion molding, injection molding or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a thermoplastic wood composition having excellent thermal fluidity and usable as an extrusion molding material.

[Conventional technology]

Synthetic resins obtained from fossil resources such as petroleum and coal are used in large quantities as industrial raw materials because they are inexpensive and can be easily processed using processing methods such as hot pressing, but there is a limit to their reserves. The depletion of these resources has become a global problem. On the other hand, wood materials such as wood have recently attracted attention as a renewable resource. However, since a wood material made by simply crushing wood cannot be hot-pressed, it is not easy to process it into any shape, especially any curved surface.

In addition, wood materials have traditionally been used for various purposes such as building materials due to their excellent characteristics, but small-diameter trees, thinned wood, and sawdust discharged from wood factories are Most of the waste is disposed of by methods such as incineration, and there is a desire to develop effective ways to use it.

In order to make these wood materials into materials that can be molded under heat and pressure, the present inventors first developed a method for producing modified wood pieces (Japanese Patent Laid-Open No.
-83806) was proposed. These modified wood chips are made by subjecting wood chips to an addition esterification reaction with a dibasic acid anhydride and a monoepoxy compound, and can be heat-press processed into hard sheets or sheets with excellent moisture and water resistance. It can be used as a board.

In addition, in JP-A-62-77903, a chemical modification in which small pieces of wood and an epoxy compound are reacted under normal pressure and without a solvent in the presence of potassium salts of fatty acids, and organic groups are bonded through ether bonds. We have developed a method for manufacturing wood materials.

However, these modified wood pieces and chemically modified wood materials (hereinafter collectively abbreviated as "chemically modified wood + O") require a temperature of 180 to 200'C, 3
It is necessary to perform hot-press molding at a considerably high temperature and pressure of 00 kg/ct or more, which is not preferable from the viewpoint of productivity and energy efficiency.

In addition to the above, research is underway to make wood materials thermoplastic, and it is said that in order to impart thermofluidity to wood materials, it is important to disrupt the crystal structure of cellulose in wood materials. It's me.

On the other hand, blasted wood is currently being considered for use as roughage for livestock, and it has been confirmed that it is comparable to conventional roughage. Research has also been conducted on structural changes in wood due to blasting treatment, and it has been reported that blasting increases the crystallinity of cellulose in wood, and that lignin becomes lower molecular due to the cleavage of allyl ether bonds. There is.

[Problem that the invention seeks to solve]

The inventors have discovered that while having a relatively high wood content,
Studies were conducted to obtain a thermoplastic wood +4 composition that has excellent thermal fluidity and can be molded under normal extrusion conditions.

[Means for solving problems]

The inventors of the present invention have conducted extensive research in view of the problems mentioned in section 2 above, and have surprisingly found that although the crystallinity of wood materials that have been subjected to blasting treatment increases due to the blasting treatment, The wood composition obtained by reacting a monoepoxy compound or a monoepoxy compound and a polybasic acid anhydride with a wood material has significantly superior thermal fluidity compared to the case where ordinary wood material is used. This discovery led to the completion of the present invention.

That is, in the present invention, 100 weights of blasted wood materials = 3
= A feature of reacting the okibe with 50 to 300 parts by weight of a monoepoxy compound, or 100 parts by weight of the blasted wood material and a total of 50 to 300 parts by weight of the monoepoxy compound and polybasic acid anhydride. The present invention provides a method for producing a thermoplastic wood composition having excellent thermal fluidity.

The method for producing a thermoplastic wood composition of the present invention includes adding 50 to 300 parts by weight of a monoepoxy compound to 100 parts by weight of blast-treated wood as a wood component, or adding 50 to 300 parts by weight of a monoepoxy compound and a polybasic acid anhydride in total. For example, a monoepoxy compound is reacted with the hydroxyl groups of the blasted wood through an ether bond in the presence of a potassium salt of a fatty acid as a catalyst. Examples include a method of adding a polybasic acid anhydride and a monoepoxy compound to the hydroxyl group of a wood material, and a method of alternately adding and esterifying a polybasic acid anhydride and a monoepoxy compound.

In these methods, if the monoepoxy compound or the total amount of the monoepoxy compound and polybasic acid anhydride is less than 50 parts by weight based on 100 parts by weight of the blasted wood material, the resulting thermoplastic wood composition has poor thermal fluidity, and for example, it is impossible to measure the melt index (Ml), which is one index of thermal fluidity. On the other hand, if the monoepoxy compound or the total amount of monoepoxy compound and polybasic acid anhydride is more than 300 parts by weight per 100 parts by weight of the blasted wood, although the thermal fluidity is excellent, the wood content is This becomes too low, which not only goes against the purpose of the present invention (but is also economically unfavorable).

The blasted wood components used in the production of the thermoplastic wood composition of the present invention are not particularly limited to logs or tree species, and include wood such as wood flour, wood fibers, and wood chips, as well as large amounts of unused wood. Examples include plant fibers such as wheat straw, rice straw, rice husk, waste paper, linters, and lignocellulose materials whose main components are cellulose and lignin, which are discarded in the field, and are pulverized after being blasted. In addition, small pieces of wood and sawdust produced by-product as industrial waste in industries that use water conservancy are blasted and pulverized, and zander powder, etc. discharged during the manufacturing process of particle boards, fiberboards, etc., is blasted and treated. can also be used.

Conversely, the above-mentioned wood material components can be processed into wood chips, wood fibers, finely divided wood powder, etc. using a pulverizer, Henschel mixer, etc., and then used by being subjected to explosion treatment. The blasting process is carried out in 3-50 kg/c+ of saturated water with 0.1
This can be done by boiling for ~30 minutes and then vigorously decompressing. If the moisture content of the wood component obtained by blasting in this way is high, it is preferable to dry it with a hot air dryer, vacuum dryer, etc. to remove the moisture to 10% or less before use. If a large amount of moisture remains in the wood components,
This water is not preferable because it reacts with the anhydride group of the polybasic acid anhydride to produce a polyhydric carboxylic acid as a by-product or opens the epoxy group of the monoepoxy compound.

The monoepoxy compound may be any compound containing one epoxy group in the molecule, such as phenyl glycidyl ether, allyl glycidyl ether, styrene oxide, octylene oxide, methyl glycidyl ether, butyl glycidyl ether, talesyl glycidyl. Examples include ether and epichlorohydrin.

Examples of polybasic acid anhydrides include maleic anhydride, succinic anhydride, phthalic anhydride, hexahydrofucric anhydride, tetrahydrophthalic anhydride, dichloromaleic anhydride, itaconic anhydride, tetrabromophthalic anhydride, and hexahydrofuric anhydride. , trimellitic anhydride, pyromellitic anhydride, etc., but maleic anhydride, succinic anhydride, and phthalic anhydride are particularly preferred because they are industrially advantageous and inexpensive.

When reacting a monoepoxy compound and a polybasic acid anhydride with blast-treated wood, the charging ratio of the monoepoxy compound and the polybasic acid anhydride is 1 equivalent of the epoxy group of the monoepoxy compound. Acid anhydride groups in substances 1.
It is preferably 5 equivalents or less.

If there are more anhydride groups in the polybasic acid anhydride than this, there will be more half esters of the polybasic acid anhydride which have carboxyl groups added to the hydroxyl groups of the wood material at the ends, and the resulting thermoplastic wood composition It is not preferable because the water resistance of 17% decreases.

When reacting blasted wood with monoepoxy compounds and polybasic acid anhydrides, the reaction proceeds satisfactorily even without a catalyst, but sodium carbonate, dimethylbenzylamine, pyridine, and tetramethylammonium chloride are used to accelerate the reaction. Alternatively, a catalyst such as a potassium salt of a fatty acid may be used, and when a monoepoxy compound is subjected to an addition etherification reaction on blasted wood, a catalyst such as a potassium salt of a fatty acid, dimethylbenzylamine, or tetramethylammonium chloride may be used as a catalyst. It is preferable to use

In the above method, about 10 to 80% by weight of the monoepoxy compound or the total amount of the polybasic acid anhydride and monoepoxy compound subjected to the reaction does not react and bind to the wood component. Produced as a by-product as oligomers.

In the present invention, this oligomer is also used as a component of the thermoplastic wood composition without being removed by extraction with a solvent or the like.

In addition, in the reaction between the blasted wood material and the monoepoxy compound, or the monoepoxy compound and the polybasic acid anhydride, the blasted wood material and the monoepoxy compound, or the monoepoxy compound and the polybasic acid anhydride. A part of the wood material that is soluble in acetone is also produced by the reaction.

Furthermore, in the production method of the present invention, a small amount of unreacted substances remain. The residual amount can be varied depending on the charging ratio of monoepoxy compound and polybasic acid anhydride, reaction temperature, reaction time, etc., but it is preferably 20% by weight or less of the entire reaction product.

In the thermoplastic wood composition produced by the production method of the present invention, the crystallinity of the blasted wood that is its raw material is higher than that of unexploded wood, so the thermal fluidity is actually reduced. It is unexpected that it has excellent thermal fluidity, even though it is expected that it will have good thermal fluidity. The cause is not clear, but lignin, which acts as a binder in wood, decomposes over 110-years by blasting the wood, and the decomposed lignin and monoepoxy compound or monoepoxy The reaction products produced by the reaction of the compound and polybasic acid anhydride and the above oligomers act as plasticizers for thermoplastic wood, resulting in significantly improved thermal fluidity compared to conventional thermoplastic wood. considered to be a thing.

As described above, the thermoplastic wood material composition obtained by the production method of the present invention not only has significantly improved thermal fluidity compared to conventional chemically modified wood materials, but also has oligomers and unused materials by-produced during its production. Another advantage is that there is no need to remove reactants by extraction with a solvent or other operations. Furthermore, small-diameter trees, thinned wood, wood chips, wood powder, etc. produced as by-products of the wood industry can be used by blasting, and are extremely useful from the standpoint of their effective utilization.

When molding the thermoplastic wood composition obtained by the production method of the present invention to make a molded article, it can be press-molded as is, or it can be processed by molding ordinary thermoplastic resins by extrusion molding, injection molding, etc. The mixture can be molded under the following conditions, but before that, it can be uniformly kneaded using a kneader such as a blender, kneader, mixer roll, Banbury mixer, etc., and then molded by the above-mentioned molding method. The molded product thus obtained is suitable as an industrial part material, a building material, etc. in many fields.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. The blasted wood flour used in these examples was dried to a moisture content of 5% or less.

Furthermore, the present invention is not limited to these Examples.

The anhydrous acid value of the product was determined from the difference between the aqueous acid value and the non-aqueous acid value.

For the aqueous acid value, add approximately 0.3 g of a precisely weighed sample to 30 m of acetone.
2 and 10 d of ion-exchanged water,
It was determined from the value obtained by titration with O, IN K OH-HzO after being left in the room for 0 minutes.

The non-aqueous acid value is determined by adding approximately 0.3 g of a precisely weighed sample to acetone 30
After dispersing in rrdl, 0. It was determined from the value obtained by titration with IN KOH-methanol.

The epoxy value is 0.1NHB per approximately 0.3g of accurately weighed sample.
Add 7 mR of r-acetic acid solution and leave in the room for 20 minutesfffL
After adding 10 ml of O,IN phenylglycidylniterulchlorobenzene solution and leaving it in the room for another 20 minutes, the value was determined by titration with 0.1N HBr-acetic acid solution.

The acetone-soluble portion refers to the oligomers that are not bonded to wood components and the wood that has become soluble in acetone.The weight of the sample (X) and the weight eluted by Soxhlet extraction with acetone (Y ) and the total weight (Z) of unreacted monoepoxy compound and polybasic acid anhydride using the following formula.

Acetone soluble part (weight%) = 100 ("1-Z)
/X melt index (MI) is JIS K
7210, it was determined from the value measured at 150°C1 test load of 10kg or 190°C1 test load of 10kg.

Example 1゜Dry wood powder of melanoxylon treated as wood material by steaming at 30 kg/c+fl for 5 minutes and then blasting treatment -13=20. 0g, 6.52 g of succinic anhydride was placed in a 500 ml four-way adjustable flask, and after reacting with stirring at 130°C for 2 hours, 23.48 g of styrene oxide was added.] At 50°C for 1 hour, The reaction was carried out at 200°C for 4 hours. Then, 0.2 potassium acetate as a catalyst for the etherification reaction.
6 g was added and heated at 150'C for 3 hours and at 200°C for 1 hour to add the remaining excess styrene oxide to the hydroxyl groups of the wood material through an etherification reaction, thereby producing the thermoplastic wood material of the present invention. A composition was obtained. Anhydrous acid value, epoxy value, weight % of acetone soluble portion by Soxhlet extraction and M after mixing roll of this thermoplastic wood composition
The values of l are shown in Table 1.

Example 2゜Example 2 except that dried melanoxylon wood flour, which had been steamed at 20 kg/cnl for 6 minutes and then exploded, was used as the wood material.
In the same manner as above, a thermoplastic wood composition of the present invention was obtained.

Table 1 shows the anhydrous acid value, epoxy value, weight percent of acetone soluble portion by Soxhlet extraction, and Ml value after mixing roll of this thermoplastic wood composition.

Comparative example 1゜Dry wood flour as wood material (product name: LIGNOCEL
5150 TR; J, Rettenmaier
&5oehne; fiber length: 30-60μ)
A wood composition was obtained in the same manner as in Example 1 except that the following was used. Table 1 shows the anhydrous acid value, epoxy value, weight percent of acetone soluble portion by Soxhlet extraction, and Ml value after mixing roll of the wood composition.

Comparative example 2 Dried wood flour (product name: LIGNOCEL) as wood material
5150 TR; J, Rettenmaier
A wood material composition was obtained in the same manner as in Example 1, except that a 120-mesh (manufactured by &5oehne) was used. Table 1 shows the anhydrous acid value, epoxy value, weight percent of acetone soluble portion by Soxhlet extraction, and MI value after mixing roll of this wood composition.

Comparative Example 3 A wood material composition was obtained in the same manner as in Example 1, except that dry red pine wood powder subjected to steaming treatment was used as the wood material. Table 1 shows the anhydrous acid value, epoxy value, weight percent of acetone soluble portion by Soxhlet extraction, and Ml value after mixing roll of this wood composition.

In Examples 1 and 2, blast-treated wood was used, and 150 parts by weight of a reactive substance containing a monoepoxy compound was reacted with 100 parts by weight of the wood components, so the resulting wood compositions were heat-resistant. It was also confirmed from the MI measurement results that the fluidity was excellent. = On the other hand, in Comparative Examples 1 to 3, 150 parts by weight of a reactive substance containing a monoepoxy compound was reacted with 0 parts by weight of wood component 1 (), but using blast-treated wood as the wood component. Because of this, it has poor thermal fluidity.

Table 1 Example 3゜Dry wood powder of melanoxylon which was steamed at 30 kg/cfl for 5 minutes and then exploded as a wood material 20. Og, 11.71 g of succinic anhydride, and styrene oxide 1,8.
Pour 29 g into a 500 ml separable flask, react at 120°C for 7 hours, and reduce the anhydrous acid value Oeq/k.
g, epoxy value 0.16 eq/kg, acetone soluble part in Soxhlet extraction 67% by weight, wood content 40
A thermoplastic wood composition of % by weight was obtained. The Ml value of this thermoplastic wood composition after mixing roll is 150
°C, load 10kg: 0.2, 190°C, load 1
．． In the case of 0 kg, it was 0.9.

Example 4: Dry melanoxylon wood powder 4, which was steamed at 20 kg/cJ for 6 minutes and then exploded as a wood material. Og and 49.10 g of phenyl glycidyl ether were charged into a 500 mβ four-separable flask, heated at 220°C for 4 hours with stirring, and then 10.90 g of succinic anhydride was added.
At 50°C for 4 hours, in order to add unreacted phenyl glycidyl ether to the hydroxyl groups of the wood in an etherification reaction, potassium acetate, which is a catalyst for the etherification reaction, was added.
．． 42 g was added and reacted at 150°C for 5 hours,
A thermoplastic wood composition having a wood base of 40% by weight was obtained. Table 2 shows the anhydrous acid value, epoxy value, weight percent of acetone soluble portion by Soxhlet extraction, and Ml value after mixing roll of this thermoplastic wood material &11 product.

Comparative example 4.

Dried wood flour as a wood material (product name: LIGNOCEL
5150 TR; J, Rettenmaier & 5
A wood material composition having a wood material content of 40% by weight was obtained in the same manner as in Example 4, except that 120 mesh (manufactured by Oehne) was used. Table 2 shows the anhydrous acid value, epoxy value, weight percent of acetone soluble portion by Soxhlet extraction, and MI value after mixing roll of this wood composition.

In Example 4, wood material subjected to blasting treatment was used, and wood material component 1
Since 150 parts by weight of a reactive substance containing a monoepoxy compound is reacted with 00 parts by weight, the obtained wood composition has excellent thermal fluidity. On the other hand, in Comparative Example 4, 150 parts by weight of a reactive substance containing a monoepoxy compound was reacted with 100 parts by weight of the wood component, but since the wood component did not use blasted wood, it lacking in sex.

Table 2 Example 5゜Dry wood powder of melanoxylon which was steamed at 20 kg/cffl for 6 minutes and then exploded as a wood material 20. Charge Og and 22.58 g of phenylglycidyl ether into a 500-gear four-piece adjustable flask, and heat at 220°C for 4 hours with stirring, then add 7.42 g of fucuric anhydride to 150 g.
°C for 4 hours, and in order to add unreacted phenyl glycidyl ether to the hydroxyl groups of the wood material in an etherification reaction, 0.2% potassium acetate, which is a catalyst for the etherification reaction, was added.
0 g was added and reacted at 150°C for 5 hours to obtain a thermoplastic wood composition with a wood content of 40% by weight. As a result of analysis, this thermoplastic wood composition has an anhydrous acid value of 0.13.
eq/kg, epoxy value Oeq/kg, and acetone soluble portion by Soxhlet extraction of 68% by weight. The Ml value of this thermoplastic wood composition after mixing rolls is:
150°C1 load 10kg 0.6.190°C1
It was 2.0 when the load was 10 kg.

Example 6゜17.5 g of dried lauan wood flour, which had been steamed at 30 kg/afl for 6 minutes and then exploded as a wood material, and 32.5 g of styrene oxide were placed in a 500 mfl four-piece separable flask and heated at 220°C. After heating with stirring for 4 hours at
．． 49 g was added and reacted at 150'C for 6 hours to obtain a thermoplastic wood composition containing 35% by weight of wood base N. As a result of analysis, this thermoplastic wood composition has an epoxy value of 0.
．． 25 eq/kg, and the acetone soluble portion was 69% by weight by Soxhlet extraction. The Ml value of this thermoplastic wood composition after mixing roll was 190"C1 and 20 at a load of 10 kg.

Examples 7-9゜ Dried lauan wood flour, which has been steamed at 30 kg/c for 5 minutes and then exploded, was used as the wood material, and charged into a 500 d four-piece collapsible flask with a monoepoxy compound.
After heating with stirring for 4 hours at °C, succinic anhydride was added to
At 0°C for 4 hours, in order to add the unreacted monoepoxy compound to the hydroxyl group of the wood material through an etherification reaction,
Add potassium acetate, which is a catalyst for the etherification reaction, and add 150
The mixture was reacted for 5 hours to obtain a thermoplastic wood composition of the present invention. Table 3 shows the anhydride acid value, epoxy value, weight % of acetone soluble portion determined by Soxhlet extraction, and Ml values of the obtained thermoplastic wood composition.

Comparative Example 5゜ Dried lauan wood flour, which had been steamed at 30 kg/cf for 5 minutes and then exploded, was used as a 5° wood material. It was charged into a 500-gear Yotsuro separable flask with butyl glycidyl ether, a monoepoxy compound, and heated at 220°C. After heating with stirring for 4 hours, succinic anhydride was added and heated at 150°C for 4 hours. Potassium acetate was added as a catalyst for the etherification reaction to add unreacted butyl glycidyl ether to the hydroxyl groups of the wood. was added and reacted at 150'C for 5 hours to obtain a wood composition with a wood content of 70% by weight. Anhydrous acid value, epoxy value, weight % of acetone soluble portion by Soxhlet extraction and M of the obtained wood composition
The values of I are also shown in Table 3.

The wood compositions of Examples 7 to 9 used blast-treated wood as the wood material, so they showed excellent thermal fluidity in the measurement of Ml, but the wood composition of Comparative Example 5 Even though blast-treated wood was used, the wood content was too high, making it impossible to measure Ml and resulting in poor thermal fluidity.

Table 3 PGE: Phenyl glycidyl ether.

BGE Nibutyl glycidyl ether.

SO: Styrene oxide.

23 One Example 40g of dried lauan wood flour, which was steamed as a 10° wood material at 30kg/c+f for 5 minutes and then exploded, was charged into a 500mβ four-separable flask with 47.96g of butyl glycidyl ether, and heated at 220°C. After heating with stirring for an hour, 12.04 g of maleic anhydride was added and heated at 150°C for 4 hours.
Furthermore, in order to add unreacted butyl glycidyl ether to the hydroxyl groups of the wood material in an etherification reaction, 0.48 g of potassium acetate was added as a catalyst for the etherification reaction, and the reaction was carried out at 150° C. for 5 hours. Material content 40
A thermoplastic wood composition of % by weight was obtained. The obtained thermoplastic wood material composition had an anhydride acid value of 0.03 eq/kg, an epoxy value of 0.06 eq/kg, and an acetone soluble portion of 58% by weight as determined by Soxhlet extraction. The MlO value of this thermoplastic wood composition after mixing roll is 150°C
In the case of 1 load of 10 kg, it was 183.

〔effect〕

As described above, the thermoplastic wood material composition obtained by the production method of the present invention has significantly improved thermal fluidity compared to conventional chemically modified wood materials. It is not only useful industrially because it can be molded by conventional molding methods such as extrusion molding and injection molding, as well as hot-press molding, but it is also useful for small diameter trees, thinned wood, and wood chips and wood powder that are by-products of the water conservancy industry. etc. can also be used by subjecting them to blasting treatment, and are extremely useful from the standpoint of their effective utilization. Further, the thermoplastic wood composition does not require post-treatment such as extraction with a solvent after the reaction, and can be used as it is for extrusion molding, etc., and is therefore extremely useful industrially.

Claims (1)

[Claims] (1) 100 parts by weight of the blasted wood material and 50 to 300 parts by weight of a monoepoxy compound, or 100 parts by weight of the blasted wood material, a monoepoxy compound, and a polybasic acid anhydride in a total of 50 to 300 parts by weight. 1. A method for producing a thermoplastic wood composition having excellent thermal fluidity, the method comprising reacting with a thermoplastic wood composition.