Process for making polybutylene terephthalate (PBT) from polyethylene terephthalate (PET)
US7902263B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2007 |
| Grant date | Mar 8, 2011 |
| Priority date | — |
| Expiry date | Jan 24, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/62
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention relates to a process for making modified polybutylene terephthalate random copolymers from a polyethylene terephthalate component. In one embodiment, the invention relates to a two step process in which a 1,4-butane diol component reacts with a polyethylene terephthalate component under conditions that depolymerize the polyethylene terephthalate component into a molten mixture and the molten mixture is placed under subatmospheric conditions that produce the modified polybutylene terephthalate random copolymers. In another embodiment, the invention relates to a three step process in which a diol component selected from the group consisting of ethylene glycol, propylene glycol, and combinations thereof reacts with a polyethylene terephthalate component under conditions sufficient to depolymerize the polyethylene terephthalate component into a first molten mixture; and where the first molten mixture is combined with 1,4-butane diol under conditions that create a second molten mixture that is subsequently placed under subatmospheric conditions that produce the modified polybutylene terephthalate random copolymers. The invention also relates to compositions made from proce…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.