公开(公告)号：US4792624A

公开(公告)日：1988-12-20

申请号：US019168

申请日：1987-02-26

Applicant: Richard Hatfield, Jr. ,  Howard R. Steele ,  Nirad N. Shah

Inventor： Richard Hatfield, Jr. ,  Howard R. Steele ,  Nirad N. Shah

IPC: C08G12/08 ,  C07C209/00 ,  C07C209/24 ,  C07C211/00 ,  C07C211/50 ,  C08G12/40 ,  C08L79/00 ,  C07C85/24

CPC classification number: C07C209/78

Abstract: 'An improvement is described in the process of preparing polymethylene polyphenyl polyamines by condensing aniline and formaldehyde in the presence of an acid catalyst. The improvement entails adding a minor proportion of a polyamine mixture comprising di(aminophenyl)methanes and oligomeric polymethylene polyphenyl polyamines, collectively known as polymethylene polyphenyl polyamines or polymeric MDA, to an intermediate stage of the condensation reaction where the various intermediately formed aminobenzylamines are present. The process lends itself to either a batch or continuous method for preparing the polyamines.The improvement is actually observed in the polymethylene polyphenyl polyisocyanates derived from the polyamines which have substantially reduced color over those polyisocyanates prepared from polyamines prepared via a prior art method. Such color improvements invariably carry over to polyurethane products derived therefrom.

公开(公告)号：US4465639A

公开(公告)日：1984-08-14

申请号：US461247

申请日：1983-01-26

Applicant: Richard Hatfield, Jr.

Inventor： Richard Hatfield, Jr.

IPC: C07C265/14 ,  C07C67/00 ,  C07C241/00 ,  C07C263/10 ,  C08G18/76 ,  C08G18/80 ,  C07C118/02 ,  C07C119/048

CPC classification number: C07C263/10 ,  C08G18/7664 ,  C08G18/8045

Abstract: Addition of controlled amounts of water to the reaction mixture produced by phosgenation of a mixture of polymethylene polyphenyl polyamines (and like polyamines produced by condensation of formaldehyde and aromatic amines) prior to complete removal of excess phosgene gives rise to the corresponding polymethylene polyphenyl polyisocyanates having significantly improved properties. Not only is the color of the product, and of polyurethane foams prepared therefrom, significantly lighter but the proportion of higher molecular weight products is significantly less and the viscosity is less. No undesirable by-products are introduced into the polyisocyanate as a result of the process.

Abstract translation: 在完全去除过量的光气之前，通过多亚甲基多苯基多胺（和类似于通过甲醛和芳族胺的缩合产生的多胺）的混合物的光气化产生的反应混合物中加入受控量的水，导致相应的多亚甲基多苯基多异氰酸酯具有显着的 改善性能。 不仅产品的颜色和由其制备的聚氨酯泡沫的颜色明显较浅，而且较高分子量产品的比例明显较小，粘度较低。 作为该方法的结果，不会将不期望的副产物引入到多异氰酸酯中。