Cyclolinear polyorganosiloxanes and method for preparing same

• US 3,944,520 A
• Filed: 04/18/1974
• Issued: 03/16/1976
• Est. Priority Date: 04/18/1974
• Status: Expired due to Term

• Current Assignee: Kuzma Andrianovich Andrianov, Natalia Nikolaevna Makarova
• Original Assignee: Kuzma Andrianovich Andrianov, Natalia Nikolaevna Makarova
• Inventors: Andrianov, Kuzma Andrianovich, Makarova, Natalia Nikolaevna
• Primary Examiner(s): Jacobs, Lewis T.
• Application Number:
  US05/461,980
• Time in Patent Office: 698 Days
• Field of Search: 260/465 R, 260/448.2 E
• US Class Current: 528/42
• CPC Class Codes: C08G 77/04 Polysiloxanes
• CPC Class Codes: C08G 77/08 characterised by the catalysts used

Abstract

Cyclolinear polyorganosiloxanes are proposed having the formula

[XC.sub.6 H.sub.4 SiO.sub.1.5 ].sub.n

Where X is F, Cl or Br and n is from 2 × 10 to 2 × 10⁴ and the method for preparing them, that consists in hydrolytic polycondensation of the starting phenyltrichlorosilane halide in an organic solvent immiscible with water at temperatures from 5° to 40°C; water is then separated and the solution of the reaction products in the organic solvent is washed with water to neutral reaction and polymerized in the presence of a nucleophilic catalyst utilized in an amount of from 0.002 to 0.25 per cent by weight, at temperatures from 80° to 250°C, with subsequent isolation of the end product. X may be in ortho, metal or para position, or mixed isomers may be used.

Claims

1. A cyclolinear polyorganosiloxane of the formula:

space="preserve" listing-type="equation">[XC.sub.6 H.sub.4 SiO.sub.1.5 ].sub.n

wherein X is selected from the group consisting of F, Cl and Br, and wherein n is 2 ×

10 - 2 ×

10⁴.