Abstract: A heat-resistant and oxidation-resistant working fluid for fluid coupling is provided by the invention in which 100 parts by weight of a methyl phenyl polysiloxane containing a relatively minor amount of phenyl groups in the molecules thereof is compounded with 0.01 to 5 parts by weight of an organopolysiloxane having at least one amino-substituted aromatic group, such as 4-(phenylamino)phenyl group, in a molecule thereof.

Abstract: A silicone-based working fluid composition capable of exhibiting greatly improved performance of boundary lubrication is obtained by admixing an organopolysiloxane fluid with a specific chlorine-containing polycyclic cyclooctene compound in a specified amount. The inventive working fluid composition is useful, for example, as a damper fluid in various damper units due to the greatly improved lubrication and excellent thermal stability as a consequence of the high heat resistance of the specific additive.

Abstract: The invention provides a silicone-based working fluid composition having improved heat resistance which comprises (A) 100 parts by weight of a base component composed of a first dimethylpolysiloxane terminated at both molecular chain ends each with a trimethylsiloxy group and a second dimethylpolysiloxane terminated at both molecular chain ends each with a silicon-bonded hydroxy group in such a proportion that the trimethylsiloxy/hydroxy molar ratio is from 95/5 to 10/90 and (B) from 0.01 to 5 parts by weight of an additive component which is a diorganopolysiloxane having imino-containing phenoxy groups, e.g. 4-anilinophenoxy group, 4-(4-anilino)anilinophenoxy group, 4-(.alpha.-naphthylamino)phenoxy group and 4-(.beta.-naphthylamino)phenoxy group, as the pendant groups on the polysiloxane.

Abstract: A highly heat-resistant silicone fluid composition is proposed which comprises a conventional silicone fluid as the base component and a small amount of an additive organopolysiloxane modified with aromatic amino-containing groups such as 4-(p-semidino)phenyl, 4-(.alpha.-naphthylamino)phenyl and 4-(.beta.-naphthylamino)phenyl groups bonded to the silicone atoms either directly or through an oxygen atom.

Abstract: Vinyl chloride polymers or copolymers having a relatively low molecular weight or degree of polymerization are prepared by a method in which an organic compound containing a mercapto group and a hydroxy or carboxyl group in a molecule is used as the chain transfer agent. Due to their very high activity, these chain transfer agents are used in amounts that are smaller than conventionally required quantities. The quality of the polymer products is satisfactory with respect to heat stability, occurrence of fish-eyes, particle size distribution, plasticizer absorption and ease of removing residual monomer.

Abstract: Vinyl chloride monomers or a monomeric mixture composed mainly of vinyl chloride is bulk-polymerized in a polymerization vessel. The inner walls and other surfaces of said vessel, coming into contact with the monomer or monomers, are coated with one or more specifically selected inorganic or organic compounds having a solubility greater than 0.5 g in 100 g of water at 25.degree. C and a boiling point higher than 60.degree. C. This bulk polymerization method serves to greatly reduce the deposition of polymer scale on the vessel walls and other surfaces. In addition the polymer scale deposited can be readily separated and removed by merely washing with water or gas under pressure. The present method provides high quality polymers.

Abstract: Vinyl chloride monomer, or a mixture thereof with a copolymerizable monomer or monomers, is bulkpolymerized so that the deposition of polymer scale on the inner walls of the polymerization vessel and other surfaces in contact with the monomer or monomers can be greatly reduced by coating them with phosphoric esters, polyphosphoric esters or their alkali metal salts before the polymerization is commenced. Clean-up operations following each polymerization run are much simplified.