SULFONYL CHLORIDES - NOVEL SOURCE OF FREE RADICALS

Novel free radicals source based on sulfonyl chlorides is discovered. The radical mechanism is confirmed by 2,3-dimethyl-2,3-diphenylbutane formation under chlorosulfonated polyethylene heating in the isopropylbenzene solution. Concerted homolytic C-S and S-Cl bond scission of chlorosulfonated polyethylene thermal degradation mechanism proved by kinetic analysis. The proof of the two bonds simultaneous breaking is provided by the threefold activation energy reduction (83 kJ/mol) in comparison to the C-S and C-Cl bond dissociation energy (280 and 286 kJ/mol respectively), the 6 orders lower preexponential factor (2,46 ∙ 10 s) in Arrhenius equation in comparison to one bond cleavage (≈10-10 s) as well as the strongly negative activation entropy value (-134 J/mol∙K).

Use of Nonlinear Optics for Assessment of Cable Polymer Aging

Polymer jackets play an important protective role in distribution cabling by providing structure and resistance to moisture, heat, and exposure to harmful chemicals. Current methods of structural assessment, such as elongation at break (E-at-B), are inherently destructive. While other non-destructive methods such as indenter evaluation are available, they are not suitable for in-service use. We propose that second harmonic generation (SHG) could provide a non-destructive means of characterizing the aging of chlorosulfonated polyethylene (CSPE) cable jackets. SHG was used to study cables previously aged and characterized by the Electric Power Research Institute (EPRI). Comparative data between the SHG results and indenter modulus tests suggest that SHG can be used to qualitatively differentiate between minimally and significantly aged CSPE cable jackets. The results of this proof-of-concept study suggest additional work that could be done to better understand the mechanisms of the aging of CSPE cable jackets and how SHG could be used to monitor the aging process.

FEATURES OF THERMOPLASTIC ELASTOMERS BASED ON CHLOROSULFONATED POLYETHYLENE

Thermoplastic elastomers based on chlorosulfonated polyethylene and high-pressure polyethylene have been created. It has been shown that developed thermoplastic elastomers have increased strength values in comparison with the parental polyethylene. The influence of the duality of the sulfonyl chloride groups reactivity of chlorosulfonated polyethylene on the structure formation has been shown.

LACQUER COATING SYSTEM BASED ON COLD DRY POLYURETHANE ENAMEL FOR PROTECTING NOSE SPINNERS OF PLANES

Recently in the aviation industry there has been an increasing demand for the development of functional paints and varnishes, in particular, for the production of coatings intended to protect aviation equipment from abrasion and erosion damaged. Coatings of this type are especially relevant for polymer products. This work is devoted to the development of a new polyurethane enamel for the protection of antenna radomes. The comparative data of fluoroplastic, polyurethane imported enamel, enamels based on chlorosulfonated polyethylene and fluorinated rubber, intended for protection of abrasive damage.