SU39292A1 - The method of obtaining artificial resin - Google Patents

Description

Cellulose benzylation is known from many patents by M. Gomberg and Bühler, L. Lilienfeld, Okada and Tadani Nakashiva, etc. But there is absolutely no data in the literature about the possibility of benzylation of the whole raw material, which usually serves to obtain cellulose, i.e. cellulose, lignin, hemicellulose, pentosano, b, tar, etc. Experiments have shown, however, that wood flour, sawdust, pond mass, etc., can be converted, like cellulose, into a completely soluble product of benzylation. For this, the benzylation process has to be carried on somewhat differently than is the case with pure cellulose. The resulting products are transparent glassy resins from light yellow to slightly brown in color, slightly aromatic, with a melting point of 80 to 150 and higher, depending on the conduct of the benzylation process, the raw material and the purification method.

These resins are soluble in mixtures: alcohol-benzene, alcohol-toluene, alcohol-acetone, etc., and experiments have shown that they are quite suitable for the manufacture of varnishes and plastics.

A deviation from the usual methods of cellulose benzylation is that the feedstock, in very small amounts, is subjected to a pre-treatment with chlorine in an aqueous solution or a solution of weak alkali in an autoclave. In some cases (pond mass), pretreatment is not even necessary, but the benzylation process needs to be carried out a little longer.

Example 1. 1000 g of sawdust previously sifted through a 200 mesh sieve. on 1 square. inch, mixed in a glass vessel with a capacity of 10 liters with 5 liters of water. Chlorine was bubbled into the mixture at ordinary temperature and continuous stirring for 2 hours. Chlorinated sawdust was pressed on a hydraulic press to double the weight and mixed with 1500 cm Z; 0 °; o-Horo caustic soda solution and left at room temperature for 24 hours. Then sawdust was pressed from alkali to triple weight in a hydraulic press, mixed with 1700 cm of benzyl chloride and heated in a flask with reflux condenser in an oil bath for 3 hours at 120 - ISO; thereafter, 50 g of dry alkali and 700 cm of benzyl chloride were introduced and reheated under the above conditions for 9 hours (if the heating process is accompanied by stirring, the benzylation time is reduced by 3. The mass gradually brightens, liquefies and becomes translucent. End cooking is recognized by the moment of solubility in an alcohol-benzene mixture (1: 3) taken from the flask of resin. When the resin is well dissolved, then steam is passed through the mass until the total free benzyl chloride is removed. rinse with water until the sodium chloride is removed, dry in a thermostat at 100 ° or in vacuum at 70-80 and sufficient pressure of 20 lN. The color of the resin is slightly brown, melting point 106. Dissolve in alcohol-benzene, alcohol-toluene and acetone-benzene mixtures Exit 1500

Example 2. 1000 2 sawdust, previously sifted through a sieve of 200 mesh per 1 square. an inch, placed in an autoclave, and 3 liters of an IVoHoro caustic soda solution were introduced thereto and heated at 140 ° C for 1 hour. Then the sawdust is squeezed out on a hydraulic press to double the weight. Squeezed sawdust is treated with 2000 cl of 30% sodium hydroxide solution and left at room temperature for 24 hours. Then sawdust is again pressed out of alkali to triple weight in a hydraulic press, mixed with 1600 cm of benzyl chloride and heated in a flask with reflux in an oil bath for 4 hours at 130. Then 50 g of dry caustic soda and 600 cm of chloride are introduced benzyl and reheat in the above conditions for 9 hours (with stirring, the heating time is reduced by V. ". The mass gradually brightens, liquefies and becomes translucent. The end of cooking is recognized by the moment of solubility in an alcohol-benzene mixture 1: 3 taken from the flask resin. When the resin dissolves well, water vapor is passed through the mass until all the free benzyl chloride is removed. The resulting product is washed with water and dried at 100 ° under vacuum at 70 - 80 The color of the resin is slightly brown. The melting temperature of the PZ. Dissolved in alcohol benzene, alcohol-toluene and acetone-benzene mixtures. Yield 1325 g.

Example 3. 3500 g of a pond mass is treated with 3000 2 20 / about a solution of caustic soda and left at room temperature for 24 hours. Then squeeze out from alkali in a hydraulic press to triple weight, mixed with 2000 cm of benzyl chloride and heated in a flask with a reverse fridge in an oil bath for 3 hours at 110 ° C, after which 25 g of dry alkali and 500 cm of chloride are introduced benzyl and heated for another 3 hours. The end of the reaction is determined by the solubility of a sample of the resin in an alcohol-benzene mixture. When the resin dissolves well, steam is passed until all benzyl chloride is removed. The resulting product is washed with water, dried at 100 ° or under vacuum at 70-80 °. The resin color is yellowish brown. Melting point 98 °. Dissolved in alcohol-benzene, alcohol-acetone, acetone-benzene mixtures. Exit 712

The subject matter of the invention.

Claims (2)

1. A method for producing synthetic resins based on benzyl cellulose zyfir, characterized in that instead of the finished cellulose pulp, raw materials, usually used for pulp production, are usually benzylated, such as: sawdust, wood flour, pond pulp, and so on. containing cellulose, lignin, and pentosans in a finely divided state, with pretreatment with chlorine or solutions of brine, wood, or without it. 2. A process according to claim 1, wherein benzylation is carried out in two steps.