Edward L. Kay

Mechanism of Smoke Inhibition by Hydrated Fillers

Abstract The smoke inhibitory activity of hydrated fillers in SBR is centered primarily in condensed-phase processes and is analogous to the generally accepted mechanism of flame retardation by the hydrates. Dissipation of heat, which disfavors pyrolysis and favors competing crosslinking reactions is probably involved. These reactions should occur chiefly among polybutadiene segments of the polymers. In addition, the smoke-suppressant efficiency of hydrated fillers should depend upon the crosslinking efficiency of the rubber. Finally, although smoke generation in latex rubber goods presents a challenge, substantial practical reductions in visible smoke can be achieved through the selection of proper hydrated fillers.

Scrap Tire Disposal

Abstract Our overall objective in presenting this review is to call attention to the very complicated nature of the entire disposal problem. The whole field of scrap-tire disposal is full of alternatives, compromises, legislation, and conflicting reports on technological success. We will present a brief historical section explaining why the disposal of scrap-tires is now a problem (challenge) and the events that lead to it. Statistics on the annual volume of scrap-rubber generated and the volume disposed of by major processes will be reviewed. Existing and proposed legislation will be presented, and the probable impact on the rubber industry discussed. We will state what we believe to be the characteristics of an ideal solution. The technical aspects of scrap-tire disposal will not be neglected. The physical, thermal, and chemical values of a scrap-tire will be presented as a basis of defining potential uses for scrap-tires. The existing and proposed uses of scrap-tires as well as processes for disposal a...

Scrap Tire Disposal Procedures

Abstract Many procedures and processes for the disposal of scrap tires are available. Because of the complexity of the whole disposal problem—e.g., collection logistics, availability and location o...

Scrap Tire Disposal Process

Abstract Experimental results are presented which indicate that scrap rubber vulcanizates, typical of todays tires, can be depolymerized to a product which is essentially a carbon black dispersion in oil. The depolymerization is free radical in nature and requires an efficient chain transfer agent to prevent hardening of the vulcanizate and to increase the rate of depolymerization. The product, termed “Depolymerized Scrap Rubber” (DSR), should be useful, particularly as a rubber compounding ingredient and as a fuel oil extender.

Antioxidant Activity of Depolymerized Scrap Rubber

Abstract Depolymerized scrap rubber (DSR) shows stabilizer activity for solution SBR rubber. It appears that the stabilizer activity of conventional rubber reclaim is due, to a significant extent, to the hydrocarbon portion.

Hydrocarbon Tackifying Resins Ex Scrap Tires

As PART OF a continuing effort to find new uses for scrap tires, an experimental program was conducted on the conversion of scrap tires into tackifying resins. A previous report [1] summarized results on the treatment of pyrolysis oil derived from the destructive distillation of scrap tires to prepare hydrocarbon tackifying resins. The work reported herein covers research effort to simplify the pyrolysis oil process. Basic scientific knowledge on the cause of tack is minimal although the effects of tack are well known. Significant research is being conducted to correct the former situation. [2] Without the desired fundamental knowledge, a somewhat empirical experimental program was followed. Known tackifying resins are generally moderate molecular weight complex mixtures of bulky molecules. Typically, tackifying resins are also thermoplastic. Commercial hydrocarbon resins are derived from aromatic compounds or mixtures of unsaturated monomers by acid or Friedel-Crafts catalysis, [3] basically by a cationic mechanism. This was our approach in the preparation of tackifying resins from scrap rubber pyrolysis oil. [1] Our experimental program for the present work was directed to treating scrap rubber vulcanizates in a manner to reduce the molecular weight to values approaching those of known tackifying resins and to cyclize the polymer fragments to obtain a bulky structure. This procedure would result in product more severely depolymerized than conventional rubber reclaim. Actually conventional reclaimed rubber has been reported to aid in the retention of uniform tack in rubber compounds. [4] Reclaim might be used more extensively