| 摘要 |
1,257,638. Polymerizable lactone polyesters. LAPORTE INDUSTRIES Ltd. 20 Feb., 1970 [20 Nov., 1968], No. 55163/68. Headings C3P and C3R. An addition-polymerizable polyester is obtained by reacting a lactone having 6 to 9 atoms in the lactone ring, not more than thirteen carbon atoms altogether and not more than two halogen substituents with an initiator in the presence of an acidic catalyst (other than trichloroacetic acid), wherein the initiator is of the general formula L-CM 2 -A-H. In this formula -A- represents -O-, -S-, -NH-, or -NR- (where R is an alkyl group having less than six C atoms), each group M is H, Cl, Br or R and L is any group having ethylenic unsaturation and containing no acid group provided that the total number of carbon atoms in the groups M, M and L, excluding any in aromatic rings, is less than 8. The temperature at which the polyester is prepared is such that little or no polymerization of the groups L occurs, preferably 35‹ to 100‹ C. The preferred lactone is #-caprolactone or a methyl #-caprolactone and the acid catalysts whose use is described and claimed in Specifications 1,201,909 and 1,210,496, e.g. p-toluenesulphonic acid, are particularly suitable. Examples 1 and 7 describe the use of #-hydroxyethyl acrylate and N-methylolacrylamide respectively as the initiator. The unsaturated polyesters may be copolymerized with monomers such as styrene in bulk or vinyl acetate in emulsion by conventional methods or may be reacted with addition polymers, e.g. P.V.C., when they act as internal plasticizers. Example 6 describes a paint based on a polyester-vinyl acetate polymer and containing also TiO 2 , methyl cellulose, sodium pyrophosphate and water. Reference has been directed by the Comptroller to Specifications 859,642, 859,643 and 859,645. |
