Claims
- 1. A process of increasing crystallinity of water-insoluble crystallizable polyester pellets in an aqueous medium which comprises crystallizing polyester pellets having a diameter of 0.5 mm to 2.0 mm and 0.5 mm to 4 mm in length in an aqueous medium at about 50.degree.-150.degree. C. containing 0.0001 to 5% by weight of at least one surface active agent capable of preventing agglomeration of said polyester pellets selected from the group consisting of nonionic surface active agents and anionic surface active agents and dewatering said polyester pellets, wherein said polyester pellets comprise from 5-60% by weight of the aqueous bath.
- 2. The process of claim 1, wherein said polyester is homopolymeric polyethylene terephthalate.
- 3. The process of claim 1 wherein said polyester has
- (a) 80 to 100 equivalent percent of the hydroxyl moieties in the polyester provided by ethylene glycol
- (b) 0 to 1 equivalent percent of the hydroxyl moieties in the polyester provided by polyol having at least 3 hydroxyl groups
- (c) 0 to 20 equivalent percent of the hydroxyl moieties in the polyester provided by diol other than ethylene glycol
- (d) 0 to 5 equivalent percent of the hydroxyl moieties in the polyester provided by monohydric alcohol
- (e) 80 to 100 equivalent percent of the carboxyl moieties in the polyester provided by terephthalic acid compound
- (f) 0 to 1 equivalent percent of the carboxyl moieties in the polyester provided by polycarboxylic acid compound having at least three carboxyl groups
- (g) 0 to 20 equivalent percent of the carboxyl moieties in the polyester provided by dicarboxylic acid compound other than terephthalic acid
- (h) 0 to 5 equivalent percent of the carboxyl groups in the polyester provided by monocarboxylic acid
- (j) 0 to 1 equivalent percent of the total hydroxyl and carboxyl moieties in the polyester provided by a hydroxy carboxylic acid having a total of at least 3 hydroxyl and carboxyl groups
- with the proviso that (a) and (e) are not both 100 percent and when (b), (f) and (j) are each 0, at least one of (c) and (g) are at least 2 equivalent percent.
- 4. The process of claim 3, wherein said surface active agent comprises an anionic surface active agent.
- 5. The process of claim 4, wherein said anionic surface active agent comprises dodecyl sodium sulfate.
- 6. The process of claim 3, wherein said surface active agent comprises a nonionic surface active agent.
- 7. The process of claim 6, wherein said nonionic surface active agent comprises polyoxyethylene sorbitan monooleate.
- 8. The process of claim 6, wherein said nonionic surface active agent comprises octylphenoxy polyethoxy ethanol.
Parent Case Info
This is a continuation of application Ser. No. 923,060, filed July 10, 1978, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
48-5258 |
Feb 1973 |
JPX |
Non-Patent Literature Citations (1)
Entry |
Schwartz et al., "Surface Active Agents and Detergents", vol. II, 1958, pp. 682-684. |
Continuations (1)
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Number |
Date |
Country |
Parent |
923060 |
Jul 1978 |
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