The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 01, 1991
Filed:
Mar. 17, 1989
Gianluigi Landoni, Milan, IT;
Carlo Neri, Milan, IT;
Enichem Synthesis, S.p.A., Palermo, IT;
Abstract
A linear copolyester, useful as a flame retardant agent, contains in its macromolecule units derived from: (a) terephthalic acid; (b) (C.sub.2 -C.sub.6)-alkylene glycol; (c) phenyl-hydroxymethylene phosphinic acid, in a mutual ratio comprised within the range of from 1:1:0.2 to 1:1:1, and is obtained by placing a linear polyester derived from terephthalic acid and a (C.sub.2 -C.sub.6)-alkylene glycol into contact with a poly(phenylhydroxymethylene phosphinate) (I): ##STR1## wherein: Ph is the phenyl radical; R is a hydrogen atom or a linear or branched alkyl radical containing from 1 to 8 carbon atoms; and D is from 2.5 to 100, under melting conditions, and for a contact time not longer than about 30 minutes. Such a copolyester contains the (c) units randomly distributed throughout the macromolecular chain, has an amorphous or partially crystalline structure as a function of its content of said (c) unit, and is useful in order to endow the linear polyesters, also in mixture with one another (polymeric alloys), with flameproof characteristics.