摘要:
A process for manufacturing high-resilient flexible urethan foams characterized by, reacting and foaming polyalkylene ether polyol and an organic polyisocyanate in the presence of a blowing agent, a surfactant and catalyst, (1) using as said polyalkylene ether polyol one which contains 2 to 10% by weight of a vinyl type polymer and in which its hydroxyl number ranges from 25 to 60 mg KOH/g, of its hydroxyl groups 20 to 70 mol% are primary hydroxyl groups and the remaining hydroxyl groups are secondary hydroxyl groups; (2) using as said organic polyisocyanate a mixture of tolylene diisocyanate with diphenylmethane diisocyanate or a crude diphenylmethane diisocyanate; and (3) using as said surfactant a mixture of a high-molecular-weight siloxane-oxyalkylene copolymer with a low-molecular-weight siloxane-oxyalkylene copolymer.
摘要:
A process for producing high resilience polyurethane foam utilizing as a foam stabilizer a combination of an organosilicone oil of average molecular weight 200-2000 composed of the blocks represented by the formula ##EQU1## (where a+b is 1 to 3, b is 0 or 1, R is methyl group, and R' is a hydrocarbon group of 3-15 carbon atoms) and a hydrocarbon oil of average molecular weight 200-2000 containing more than 20 wt. % of alicyclic hydrocarbon and/or aromatic hydrocarbon.
摘要:
The present invention relates to a double packages for preventing caking of powders or granules which comprises an inner container having high water vapor permeability for packaging article, an outer container having no or low water vapor permeability for packing said inner container, and desiccants placed between said inner container and said outer container.