Patent
Method for preparing vinyl halide polymers having improved processing characteristics and polymers prepared thereby
Leonard Feiler,Sheldon F. Gelman +1 more
TLDR
In this paper, a polyvinyl chloride (PVC) is prepared by partially polymerizing a VH monomer at a first reaction temperature, and then changing the reaction temperature and continuing the polymerization at a second temperature conducive to forming a polymer of an average molecular weight range different from that obtainable at the first this paper.Abstract:
Vinyl halide polymers, preferably polyvinyl chloride, which exhibit improved processing characteristics without sacrificing physical properties are prepared by partially polymerizing vinyl halide monomer at a first reaction temperature and then changing the reaction temperature and continuing the polymerization at a second temperature conducive to forming a polymer of an average molecular weight range different from that obtainable at the first reaction temperature. The product provides the physical characteristics of polymer blends but can be processed without formation of fish eyes.read more
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Polytetrafluoroethylene fine powder and process for producing the same
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Process for preparing polytetrafluoroethylene fine powders
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Patent
Process for the production of a polyvinyl-chloride (PVC) resin
TL;DR: In this article, a process for the production of polyvinyl chloride (PVC) having a median grain size of from 10 to 80 μm by suspension polymerization of vinyl chloride is described, the process comprising the following process steps: (a) introduction of water, initiator(s), optionally one or more further adjuvants, and some of the vinyl chloride into a container as initial charge and mixing of the constituents; (b) dispersion, and addition of oneor more suspension auxiliaries with continued dispersion; heating of the mixture; (d)
Patent
Method for improving synthesis efficiency of polyvinyl chloride resin
TL;DR: In this article, a method for improving synthesis efficiency of polyvinyl chloride resin is presented. But the method is characterized in that a constant-temperature polymerization process is adopted in polyvinylene chloride polymerization, and specifically comprises the steps of performing high-temperate treatment on a water phase containing an initiating agent before polymerizing, and performing constant-time treatment for 10-60 minutes after heating to the temperature which is 1-50 DEG C higher than than the needed temperature of the constant-Temperature polymerisation process.
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Patent
Polymerization catalyst for vinyl chloride
TL;DR: In this article, a process for preparing granular vinyl chloride polymers comprises agitating in a closed reaction vessel a suspension of 100 parts of vinyl chloride in 100 to 400 parts of an aqueous medium containing a suspension stabilizer, introducing 0,005 to 0,100 parts of a preformed dialkyl peroxy dicarbonate and heating the suspension at 100 DEG to 160 DEG F.
Patent
Polymercaptan modifier vinyl halide polymers
TL;DR: In this paper, the authors used a mixture of 100% VINYL CHLORIDE and other ETHYLENICALLY UNSATURATED MONOMERS in three large-scale mercantan groups.
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Method for preparing vinyl halide homopolymers having improved processing characteristics
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