Production of an improved non-reinforced polyoxymethylene molding composition which forms reduced mold deposits upon molding
US4293469A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 28, 1977 |
| Grant date | Oct 6, 1981 |
| Priority date | — |
| Expiry date | Oct 28, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L79/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The mold deposit problem commonly associated with non-reinforced polyoxymethylene molding compositions which creates a non-uniform surface on a molded article effectively is minimized. The polyoxymethylene polymer initially is heated (as described) while in admixture with about 0.25 to about 3 percent by weight based upon the weight of the polyoxymethylene polymer of a certain polycarbodiimide. The polycarbodiimide contains at least three carbodiimide units per polycarbodiimide molecule and is derived from one or more aromatic diisocyanates which are unsubstituted or are substituted with up to one methyl substituent on each aromatic ring.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.