Increasing wet strength of mouldings based on cellulose@ paper etc. - by impregnation with a soln. of oil-in-water emulsion contg. water-insol. (co)polymers, prepolymers, oligomers or monomers

摘要

A process for increasing the wet strength of moulded or pressed prods. made of cellulose, paper, straw or derivs. thereof (I) comprises impregnation with a soln. of one or more water-insol. polymers, copolymers, oligomers, prepolymers or monomers (II) in organic solvent (III), or with an oil-in water emulsion contg. (II) dissolved in the organic phase. USE/ADVANTAGE - Impregnation with water-insol. polymer etc. renders the cellulose water-repellent and prevents penetration of water into moulded fibre composites etc. This greatly increases the wet strength of the prod. and considerably extends the range of application of such prods., e.g. as substitutes for plastic mouldings in the automobile industry. The process does not suffer from the disadvantages and high costs of prior-art resin-impregnation processes associated with the use of toxic and environmentally harmful chemicals such as formaldehyde and epichlorhydrin.