Patent GB-1432711-A (GB)
Title: Process for the production of materials which contain lingo cellulose
IPC: C08L75/04
Filed: 1974-05-22
Abstract: 1432711 Moulding plastic substances; veneer panels BAYER AG 22 May 1974 [22 May 1973] 22823/74 Headings B5A and B5L [Also in Division C3] A process for the production of a polyisocyanate treated lignocellulose-containing material by compression moulding in a moulding press is characterized by using a compound which catalyses the formation of isocyanurates from isocyanates as a mould release agent. The mould release agent which may be used in an amount 0À1-50% by weight based in the isocyanate may be a quaternary ammonium hydroxide, an alkali metal hydroxide, an alkali metal alcoholate, an alkali metal salt of a carboxylic acid or a phenol, an N-alkylethyleneimine, tris-2-didiethylaminopropylhexahydro-s-triazine, a non- basic metal salt of a carboxylic acid, e.g. lead octoate, potassium phthalimide, or guanidines of the formula R 1 R 2 NC(=NX)-NR 3 R 4  and/or isobiguanidines of the formula in which formulµ the groups R 1  to R 10  and X are hydrogen, alkyl or aryl. In addition Mannich bases of condensable phenols and the aryl urethanes of these compounds obtained by reacting these Mannich bases with isocyanates may be used. Numerous specific isocyanurate catalysts are specified in the examples. The compound which catalyses the formation of the isocyanurates may be used in conjunction with a material which does not polymerize isocyanates, e.g. 1,4 - diazabicyclo - (2,2,2) - octane, N,N- dimethylbenzylamine, stannooctoate, dibutyl tin dilaurite, certain tertiary amines, an epoxide, a phenyl-glycidyl ether or a diglycidyl ether of 2,2 - bis - 4 - hydroxyphenylpropane. The process finds particular application in the manufacture of boards or mouldings from powders, fibres, chips of wood, straw, flax, sisal, hemp, sugarcane, bagasse, savanna grass, bamboo, peanut shells, rice husks and cork scrap. In addition boards or mouldings, which may be multi-layered, of veneer, paper or lignocellulose fabrics are impregnated with the isocyanate based binder and then pressed at elevated temperature. The mould release agent may be added either at the same time as the binder or separately, optionally with the addition of solvents. The polyisocyanate may be one of those conventionally used and urea-formaldehyde, melamine-formaldehyde and phenolformaldehyde binders may also be present. The examples refer to the formation of braids, which may be multi-layered from wood chips, wood chips and straw, straw, wood chips and vice husks, sugarcane bagasse, defibrator material may be a "mould release agent" selected from (a) a mixture of N-phenylcarbamic acid- (2 - dimethylaminomethyl - 4 - isononyl) - phenyl ester and N - phenylcarbamic acid (2- isononyl - 4 - dimethylaminomethyl) - phenyl ester; (b) a mixture of N - cyclohexylcarbamic acid (2 - dimethylamino - methyl - 4- isononyl) - phenyl ester and N-cyclohexylcarbamic acid (2-isononyl-4-dimethylaminomethyl)phenyl ester; (c) a mixture of N-cyclohexylcarbamic acid (2 - di - n - butylaminomethyl. 4 - isononyl) - phenyl ester and N - cyclohexylcabamic acid (2 - isononyl - 4 - di - n - butylaminomethyl) - phenyl ester; (d) N - n - propylcarbamic acid (2 - dimethylaminomethyl- 4,6 - dimethyl) - phenyl ester; (e) benzoic acid (2 - dimethylaminomethyl - 4,6 - dimethyl)- phenyl ester; (f) hexahydrotriazine; and (7) potassium salt of coconut fatty acid. Besides other resin ingredients a fungicide, paraffin emulsion and ammonium phosphate may also be present. Examples 9 and 10 refer to forming veneer panels from birch veneers using either N-npropylcarbamic acid (2 - dimethylaminomethyl - 4,6 - dimethyl) - phenyl ester or potassium salt of coconut fatty acid as mouldrelease agent.