US2495234A - Method of treating cellulosic materials with trimethylolphenol - Google Patents

Description

Patented Jan. 24, 1950 METHOD OF TREATING CELLULOSIC MATE- .RIALS WITH TRIMETHYLOLPHENOL Nicolas Drisch and Item: Fays, Paris, France, al-

signors to Comptoir des Textiles Artiflciela, a corporation of France No Drawing. Application February 23, 1946 8Q- rial No. 649,780. In France June 5, 1944 Section 1, Public Law 690, August 8, 1946 Patent expires June 5, 1964 12 Claims.

This invention relates to the manufacture of artificial products derived from cellulose. More particularly, it relates to a method of improving the physical properties of synthetic textiles derived from cellulosic materials. Specifically, it relates to treating the synthetic textile material in the form of dense masses.

Copending application Serial No. 649,777, filed on even date herewith, entitled Cellulose derivatives and process of preparing same," discloses a process for preparing new cellulose derivatives, called resyl cellulose, by the formation of bridge linkages between cellulose chains by means of resiniferous compounds, more especial- 1y bior polymethyloloxyaryls, and the general application of this process to the manufacture of variousproducts.

Copending application Serial No. 649,778, filed on even date herewith, entitled Shaped synthetic products and method of making same," and copending application Serial No. 649,779, filed on even date herewith, entitled Method of treating preformed shaped structures," disclose the application of the aforementioned process to the manufacture of synthetic products, and particularly viscose rayon yarn.

In the process disclosed in the aforementioned applications, the bridge linkages are converted into resiniform linkages by heating, preferably in the presence of suitable catalysts. containing the resiniform linkages are characterized inter alia by swelling to a degree considerably lower than that of the untreated cellulosic material.

When the aforementioned processes were applied to dense masses of artificial textiles, such as rolls of rayon goods or compressed bales of staple fiber, the thermal treatment was eifected by means of hot air. Such procedure did not produce materials which had substantially uniform properties throughout the mass of the goods. Usually, the material at the outside of the bale swelled in water materially less than the material at the center of the mass.

Additionally, the fiber was characterized by an undesirable yellow coloration.

An object of this invention is to provide a new method of thermally treating cellulosic materials containing free hydroxyl groups and impregnated with a bior poly-functional resiniferous Products compound which, under the influence of heat, will form resiniform bridge linkages between cellulose chains.

Another object of this invention is to provide a method of thermally treating dense masses of cellulosic materials containing free hydroxyl groups and impregnated with a bior poly-functional resiniferous compound which, under the influence of heat, forms resiniform bridge linkages between cellulose chains to impart improved and substantially uniformly reduced swelling characteristics throughout the mass.

Other and additional objects will become apparent hereinafter.

The above objects are accomplished, in general, by subjecting dense masses of textile materials, comprising cellulosic material having free hydroxyl groups and impregnated with a bior poly-functional resiniferous compound which, under the influence of heat, will form resiniform bridge linkages between cellulose chains, to the action of dry saturated steam under pressure. The dry steam serves as a heat carrier and has the advantage of effectively and easily penetrating the dense mass. Preferably, the dry steam is deaerated and, preferably also, prior to the treatment of the mass with the dry steam, the mass is subjected to the action of a vacuum.

The details and manner of practicing the invention will become apparent by reference to the following specific examples, it being understood that these examples are merely illustrative embodiments of the invention and that the scope thereof is not in any way limited thereto. Throughout the examples, the proportions of the ingredients are parts by weight.

Example 1 To a viscose solution having a cellulose content of 7% and a caustic soda content of 6.5% was added 15% (based on the cellulose) of the product of controlled (partial) condensation of trimethylolphenol obtained by heating the trimethylolphenol at from 96 C. to 98 C., in the presence of lactic acid, for several hours, this product being dissolved in its own weight of an aqueous 6% caustic soda solution. After homogenization and ripening the resulting viscose to a salt number of 5, it was spun into an acid bath of the "Muller' type through a spinneret having 1000 orifices at a rate giving a unit standard of 4 denier (metric number 2250). The yarn was stretched, washed with water, and then desulfured by an aqueous solution containing 10 grs. per liter of sodium suliite. The desulfured yarn was thoroughly washed and then impregnated with an aqueous solution containing grs. per liter of an anion active derivative of a long chain fatty acid. The material was cut into pieces 100 mm. long, which were subjected to an opening treatment in an opener, and the resultant fiufi dried under a temperature in the neighborhood of 90 C. The staple fiber at this stage had a swelling in water of the order of 85%.

The staple fiber was baled under pressure into identical bales of 100 kg. One of the bales was introduced into a horizontal autoclave and subjected to the action of a vacuum, the final pressure being 60 mm. of mercury. Then dry steam, preferably de-aerated and under.2 kg. per square centimeter pressure, was introduced into the autoclave and allowed to act for 2 hours. The temperature was 120 C. correspondin to the pressure of 2 kg. per square centimeter. At the end of this period of time, the swelling of the material in water was reduced to 45% uniformly throughout; the bale. The fiber had a slightly yellow color.

Another of the identical bales, prepared as previously described, was heated with hot air at 130 C. for 2 hours. At the end of this time, the fibers at the outside of the bale swelled in water 48%, while the fibers at the center of the bale swelled in water 75%. The fibers resulting from this treatment had a pronounced yellow color, specially at the surface of the bale.

, Example 2 Staple fiber (regenerated cellulose) of 4 denier (metric number 2250) was treated in an aqueous bath containing 30 grs. per liter of trimethylolphenol prepared according to the method of Manasse and Lederer (Berichte der deutschen chemischen Gesellschaft, 1894, vol. 27, p. 2409). The fiber was passed into a drier, and after drying it had a swelling of 110%.

The fiber was compressed into bales of 100 kg., and a bale of material was treated with dry steam under a pressure of 2 kg. per square centimeter under the same conditions as those set forth in Example 1. The product of this treatment swelled 54% substantially uniformly throughout the mass without any appreciable yellow coloration.

Herein, the term swelling or equivalent terminology is defined as the percentage of water retained by the dry material after impregnation with water and drying for minutes in a centrifugal drier cm. in diameter and rotating at 3,000 R. P. M.

The trimethylolphenol utilized in Example 2 is prepared in accordance with the method of Manasse and Lederer above referred to, wherein phenol is condensed with formaldehyde, in the form of formol, in the proportion of 3 mols of formaldehyde per phenol radical, in the presence of an alkaline medium, such as caustic soda, lime, organic bases. etc., at moderate temperatures, for example not exceeding 65 C., th reaction being completed in about 2 hours. At ordinary temperature (20 C.), the reaction will take 48 hours. The end of the reaction is marked by complete absorption of the formol. The alkali is then carefully neutralized. Formation of resinous products must be avoided. The reaction product is a mixture of the phenyl diand trl-alcohol, the latter (trimethylolphenol) preponderating and being present in an amount of more than When a different phenolic derivative is employed as the raw material, the poly-alcohol phenol is prepared in a similar manner to that'previously described except that the quantity of formol is determined by calculation of the maximum number of methylol radicals which can be fixed to the nucleus of the phenolic derivative used. The resulting product is a polymethylolphenol consisting essentially of trimethylolphenol, as explained in co-pending application Serial No. 649,777, above identified.

The partially condensed trimethylolphenol used in Example 1 is obtained by a controlled condensation of the product produced above by the Manasse and Lederer process. Specifically, the reaction product of Manasse and Lederer is condensed by heating it at from 96 to 98 C. for several hours in the presence of lactic acid, the final product being soluble in aqueous solutions of caustic soda, as fully described in copending application Serial No. 649,778.

The polymethylolphenols are the simplest of the resiniferous compounds which have proven to be the most suitable resiniferous compounds. The invention, however, is not restricted to polymethylolphenols. In general, any bior polyfunctional resiniferous compound, and more especially bior polymethyloloxyaryls, which in the presence of heat and preferably in the presence of an acid catalyst form resiniform bridge linkages by etherification of the hydroxy groups of the cellulose material and internal condensation, and having the following general formula, can be used:

(CH OH).

in which R is an aryl group, either cyclic or polycyclic, R is an alkyl, aryl, acyl group or hydrogen, and n is at least 2. The radical R may comprise two or more phenyl groups combined by direct saturation of their valences or by an oxygen, carbonyl, amine, hydrocarbon, etc. bridge. It may also comprise polycyclic groups themselves combined as shown above.

As is shown by the specific examples, the resiniferous compound may be be incorporated into the solution from which the yarn is formed, or it may be applied to a preformed yarn or fiber. When applied to a preformed structure, the resiniferous compound is preferably applied in an aqueous solution, though it can be applied from a nonaqueous solution as disclosed in the aforementioned copending application Serial No. 649,779.

The dry saturated steam employed in the process is preferably substantially free of oxygen, or the oxygen content is reduced to a minimum. Satisfactory results are obtained when de-aerated dry steam is used.

The temperature at which the reaction is carried out is not of great importance. Manifestly, it should not be so high that the cellulosic material will be deleteriously afiected.

In the preferred embodiment of the invention, as shown by the specific examples, the reaction is carried out in the absence of a catalyst. However, an acid catalyst can be used if desired, and, when used, the temperature and times of the thermal treatment are correlated to give the best results. When an acid catalyst is to be used in procedures wherein the reslniferous compound is incorporated in situ during the spinning of the filament, the catalyst can be incorporated as disclosed in copending application Serial No. 649,778. When the catalyst is to be incorporated in a preformed structure, it can be incorporated as disclosed in copending application Serial No. 649,779.

French application No. 490,205, for Process of treating absorbent textiles especially those of regenerated cellulose, discloses a process of treating cellulose hydrate materials with steam for reducing the swelling of such materials in water. The processes of the aforementioned applications Serial Nos. 649,777, 649,778, and 649,779, also result in materially reducing the swelling of the product. The reduction in swelling of cellulosic materials has been the subject of research for many years and, though it has not yet been determined if the action of the steam and the resiniferous compounds are cumulative, nevertheless it has been determined that to obtain the same final swelling the operating temperature is lower, or the duration of the treatment is shorter, or the catalyst present is less active, in the case of thermal treatment with dry saturated steam as herein described than that with hot air.

Though the invention has been described in connection with dense masses of staple fiber, it is not restricted thereto since it is manifest that the invention can be applied to other masses. The invention can be applied to rolls of fabric made of yarn having the resiniferous reagent incorporated therein. Similarly, the invention can be applied to dense skeins of yarn in which the resiniferous reagent has been incorporated.

The dense mass is preferably formed of regenerated cellulose yarn or fiber obtained by the viscose process. However, the invention is not restricted thereto. The yarn or fiber may be obtained from solutions of cellulosic derivatives containing free hydroxyl groups, such as hydroxyalkyl or glycol cellulose, cellulose carboxylic acids, slightly etherified methyl and ethyl cellulose, etc. It also can be obtained from dry spinning of cellulosic derivatives.

Since it is obvious that various changes and modifications may be made in the above description without departing from the nature or spirit thereof, this invention is not restricted thereto except as set forth in the appended claims.

We claim:

1. A method which comprises subjecting a dense mass of cellulosic material, having free hydroxyl groups and having incorporated therein a non-resinous polymethylolphenol consisting es- .sentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to dry saturated steam under pressure.

2. A method which comprises subjecting a dense mass of cellulosic material, having free hydroxyl groups and having incorporated therein a nonresinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to dry saturated steam substantially free of oxygen and under pressure.

3. A method which comprises subjecting a dense mass of cellulosic material, having free hydroxyl groups and having incorporated therein a nonresinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to dry de-aerated saturated steam under pressure.

4. A method which comprises subjecting a dense mass of cellulosic material, having free hydroxyl groups and having incorporated therein a nonresinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will formresinous bridge linkages between the cellulose chains, to a vacuum, and then subjecting the resulting mass to dry saturated steam under pressure.

5. A method which comprises subjecting a dense mass or cellulosic material, having free hydroxyl groups and having incorporated therein a nonresinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to a vacuum, and then subjecting the resulting mass to dry saturated steam substantially free of oxygen and under pressure.

6. A method which comprises subjecting a dense mass of cellulosic material, having free hydroxyl groups and having incorporated therein a nonresinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to a vacuum, and then subjecting the resulting mass to dry de-aerated saturated steam under pressure.

7. A method which comprises subjecting a bale of staple regenerated cellulose rayon fibers, having incorporated therein a non-resinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to dry saturated steam under pressure.

8. A method which comprises subjecting a bale of staple regenerated cellulose rayon fibers, having incorporated therein a non-resinous polymethylolphenol consisting essentiallyof a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to dry saturated steam substantially free of oxygen and under pressure.

9. A method which comprises subjecting a bale oi. staple regenerated cellulose rayon fibers, having incorporated therein a non-resinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains. to dryde-aerated saturated steam under pressure.

10. A method which comprises subjecting a bale of staple regenerated cellulose rayon fibers, having incorporated therein a non-resinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to a vacuum, and then subjecting the resulting bale to dry saturated steam under pressure.

11. A method which comprises subjecting a bale of staple regenerated cellulose rayon fibers, having incorporated therein a non-resinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to a vacuum, and then subjecting the resulting bale to dry saturated steam substantially free of oxygen and under pressure.

12. A method which comprises subjecting a bale of staple regenerated cellulose rayon fibers, having incorporated therein a non-resinous polymethylolphenol consisting essentially of a trimethylolphenol which upon heating will form resinous bridge linkages between the cellulose chains, to a 8 vacuum. and then subjecting the resulting bale Number Name Date to dry de-aerated saturated steam under pressure- 2,190,672 Meharg Feb. 20, 1940 NICOLAS DRISCH. 2,288,695 Fuller July 7, 1942 RENE FAYS. 2,338,983 Thackston et a1. Jan. 11, 1944 I REFERENCES CITED FOREIGN PATENTS Number Country Date gggfi m the 437,642 Great Britain Nov. 4, 1935 484,691 Great Britain Aug. 4, 1936 UN TE STATES PATENTS 10 547,846 Great Britain Sept. 15, 1942 Numb? Name Date 92 OTHER REFERENCES I $1 ,22 Emai 3? 1 g Granger: Condensation of Phenols with Form- 2088227 Battye g; July 1937 aldehyde," I, and Eng. Chem, vol. 24, No. 4 (April 2,093,651 Widmer Sept.21,1937 l93m'pages 442-447- 2 .13'7,465 Thackston Nov. 22, 1938

Claims (1)

1. A METHOD WHICH COMPRISES SUBJECTING A DENSE MASS OF CELLULOSIC MATERIAL, HAVING FREE HYDROXYL GROUPS AND HAVING INCORPORATED THEREIN A NON-RESINOUS POLYMETHYLOLPHENOL CONSISTING ESSENTIALLY OF A TRIMETHYLOLPHENOL WHICH UPON HEATING WILL FORM RESINOUS BRIDGE LINKAGES BETWEEN THE CELLULOSE CHAINS, TO DRY SATURATED STEAM UNDER PRESSURE.