- Preparing method for multi-mercapto carboxylic ester
-
The invention provides a preparing method for multi-mercapto carboxylic ester. The preparing method comprises the steps that mercapto carboxylic acid and polyhydric alcohol react under the conditions that the pressure intensity is smaller than or equal to -0.07 MPa and the temperature ranges from 80 DEG C to 100 DEG C, and multi-mercapto carboxylic ester is obtained. According to the preparing method, the esterification reaction of mercapto carboxylic acid and polyhydric alcohol is carried out under the conditions of the high temperature and negative pressure, and a water-carrying agent is not needed, so that a series of problems brought by the water-carrying agent are solved, the loss of the water-carrying agent is avoided, the reaction speed is increased, and meanwhile the product quality is improved.
- -
-
Paragraph 0075; 0076
(2017/02/17)
-
- Organic thiol metal-free stabilizers and plasticizers for halogen-containing polymers
-
Organic thiol compounds based on pentaerythritol and dipentaerythritol are described herein. More specifically, the compounds of the present invention are mixed esters of pentaerythritol and dipentaerythritol having at least one sulfhydryl group and preferably a plurality of sulfhydryl groups as well as at least one non-thiol-containing group. The organic thiol compounds are utilized to plasticize and/or heat stabilize halogen-containing polymer compositions especially poly(vinyl chloride) compositions. The compositions are substantially free or free of metal-based stabilizers, Lewis acids and terpenes. The compounds of the present invention are ideally utilized in polymers normally susceptible to deterioration and color change which can occur during processing of the polymer or exposure of the polymer to certain environments and surprisingly also serve as excellent plasticizers.
- -
-
Page/Page column 10
(2010/02/11)
-
- Multiarm organic compounds for use as reversible chain-transfer agents in living radical polymerizations
-
Generic approaches to the synthesis of multi-thiocarbonyl thio compounds are described. A multi-hydroxy core was condensed with either α-bromophenyl acetic acid or 2-mercaptopropanoic acid in the presence of p-toluenesulfonic acid catalyst to afford the corresponding esters in quantitative yield. Treatment of the bromo esters with sodium methyl trithiocarbonate or the thiols with carbon disulfide, benzyl bromide and triethylamine then affords two series of trithiocarbonates. The process is exemplified by application to mono, di- or tri-pentaerythritol. These multi-thiocarbonyl thio compounds have application as chain-transfer agents in reversible addition fragmentation chain-transfer (RAFT) polymerization as precursors to star polymers.
- Mayadunne, Roshan T.A,Moad, Graeme,Rizzardo, Ezio
-
p. 6811 - 6814
(2007/10/03)
-
