摘要:
A polyurea resin molding composition for RIM use comprising (a) polyoxyalkylenpolyamine having an average molecular weight greater than about 400 and a plurality of terminal primary or secondary amino groups, (b) an aromatic polyamine and/or xylylenediamine and (c) a polyisocyanate. The component (a) contains dispersed therein a polymer prepared by the in situ polymerization of at least two different olefinically unsaturated monomers in the presence of a radical polymerization initiator, the ratio of the average amino equivalent of said polyamines (a) and (b) in combination to the average NCO equivalent of said polyisocyanate (c) being between about 1:0.7 to 1:1.5.
摘要:
A stable polymer dispersion in polyoxyalkylenepolyamine is provided by the in situ polymerization of at two different monomers selected respectively from (a) a first monomer capable of forming a homopolymer which does not precipitate out upon the in situ polymerization and (b) a second monomer capable of forming a homopolymer which precipitates out upon the in situ polymerization. The dispersion is useful as a raw materials of polyurea RIM, forms, elastomers and other products.
摘要:
A polyurea resin molding composition for reaction injection molding use which comprises (a) a polyoxyalkylenepolyamine, (b) an aromatic polyamine and/or a xylylenediamine and (c) a polyisocyanate, wherein either one or both of components (a) and (b) have been modified by a Michael reaction with an unsaturated compound of the formula CH.sub.2 .dbd.C(R)--Y wherein R is H or CH.sub.3 and Y is an electron attracting group. The use of such modified polyamine(s) improves in-mold flow and green strength characteristics.
摘要:
Trifunctional polyoxyalkylene polyamines having a plurality of 2-alkoxycarbonylethylamino groups at terminals are produced by reacting the corresponding primary amines with an alkyl acrylate. The trifunction secondary polyamines thus produced have a moderate reaction rate with a polyisocyanate component in polyurea RIM.
摘要:
Polyoxyalkylene polyamine or aromatic diamines or xylylenediamines are modified by them to the Michael reaction with an ethylenically unsaturated monomer having an electron-withdrawing group to convert the primary amino groups at least in part to a secondary amino group of the formula:--NH--CH.sub.2 --CH(R)--Ywherein R is a hydrogen atom or methyl, and Y is an electron-withdrawing group. The modified amines find use in the manufacture of plastics such as polyurea elastomers or polyurea RIM.