No abstract

At present, cis-1,4-polyisoprenes of grade SKI-3 (GOST 14925-79) and SKI-3S (TU 2294-022-48158319-2001) are being produced in Russia. The antioxidants used for their stabilisation are given in Table 1. Antioxidants DPPD, Diaphen 13, Santofl ex 134 PD, Flexon 11L, and Dusantox L comprise N,N′-substituted p-phenylenediamines or their mixtures [1, 2]. These products are produced by various companies and are imported. Apart from DPPD, they are liquids with good solubility in toluene, and Santofl ex 134 PD, Flexon 11L, and Dusantox L have fairly good solubility in an isopentane-isoprene mixture. VTS-60, S-789, and AFA-1 are home-produced antioxidants. VTS-60 and S-789 are also p-phenylenediamine derivatives. Antioxidant Novantox 8 PPDA is analogous to S-789 [3] but, unlike it, is produced from individual 2-ethylhexanol. Antioxidant AFA-1 is the condensation product of alkylphenol, urotropin, and N-isopropyl-N′-phenyl-p-phenylenediamine [4]. Agidol-1 comprises 2,6-di-tert-butyl-4-methylphenol. Agidol-2, Lovinox 22M46, and Ralox 46 are trade names for phenolic antioxidant 2,3-methylenebis(6-tert-butyl-4methylphenol) produced by various companies.

No abstract

Reactions of isoprene rubber with maleic acid monoesters are accompanied with a sharp increase in the strength properties of raw rubber mixes, exceeding the corresponding characteristics of natural rubber. Modified and standard rubbers hardly differ from one another in their molecular and plastoelastic characteristics and also in their rheometric properties. Considerably greater tear strength and decorative properties of highly cohesive polyisoprene has been observed.