摘要:
The instant invention relates to hydroxyl polyethers which are modified with amide groups and a method of their manufacture. The method includes a first stage wherein a portion of the hydroxyl groups of a polyether polyol are aminated and a second stage wherein the amine groups are reacted with a carboxylic acid, its anhydride, ester or halide. The modified polyesters may be used for the production of polyurethane resins.
摘要:
This invention relates to new high molecular weight polyurethanes which contain a very small amount of urethane and urea groups. These new synthetic resins are built up as block copolymers and contain relatively high molecular weight segments which are derived from high melting and low melting polyols and linked together through ester and/or urethane and/or urea groups.
摘要:
This invention relates to new high molecular weight polyurethanes which contain a very small amount of urethane and urea groups. These new synthetic resins are built up as block copolymers and contain relatively high molecular weight segments which are derived from high melting and low melting polyols and linked together through ester and/or urethane and/or urea groups.
摘要:
The instant invention relates to an improved process for the production of cellular or non-cellular polyurethane urea elastomers, in which diamines which contain ester groups are used as chain lengthening agents. A characteristic feature of the process according to the invention is the use of salts of aromatic diaminocarboxylic or sulphonic acids as a portion of the chain lengthening component. Elastomers produced by this process are distinguished by their improved mechanical properties, in particular their increased tensile strength and tear propagation resistance as well as their reduced permanent elongation.
摘要:
This invention relates to a process for making optionally cellular cross-linked elastomeric polyurethane resins from(a) polyisocyanates,(b) higher molecular weight polyhydroxyl and/or polyamino compounds containing filler particles,(c) chain lengthening agents and, optionally,(d) blowing agents, catalysts and other additives known per se,Wherein filler particles capable of being cross-linked with the formaldehyde are used and wherein the elastomeric polyurethanes which contain fillers are cross-linked with formaldehyde or formaldehyde releasing compounds, after the chain lengthening reaction has been substantially completed.
摘要:
Novel, finely divided, redispersible dispersions of high melting polyesters in low melting polyhydroxyl compounds are disclosed. Disclosed also is a process for their preparation and their use as polyol components containing fillers in the production of cellular or non-cellular polyurethanes.
摘要:
The instant invention relates to compositions containing both amino groups and hydroxyl and/or mercapto groups. The products are obtained by reacting relatively high molecular weight polyols and/or polythiols with less than equivalent quantities of isatoic acid anhydride in two reaction stages.
摘要:
The invention relates to compositions containing both amino groups and hydroxyl and/or mercapto groups. The products are obtained by reacting relatively high molecular weight polyols and/or polythiols with less than equivalent quantities of isatoic acid anhydride.
摘要:
The invention relates to compositions containing both amino groups and hydroxyl and/or mercapto groups. The products are obtained by reacting relatively high molecular weight polyols and/or polythiols with less than equivalent quantities of isatoic acid anhydride.
摘要:
A process for preparing 4,4'-dinitro-diphenyl carbonate which comprises adding to a sulfuric acid solution of diphenyl carbonate maintained at a temperature between -40 and +40.degree. C a nitric acid in a stoichiometric or slight stoichiometric excess.