A rotational isomeric state model with neighbor interactions is used to calculate mean-square unperturbed dimensions and dipole moments for vinyl chloride chains CHa-(CHCI-CH,,)zH having degrees of polymerization x ranging from 1 to 150 and stereochemical structures ranging from perfect syndiotacticity to perfect isotacticity. Conformational energies used in the calculation were those which had...

tin(ii)-ion-selective electrode consisting of dibenzo-18-crown-6 (db18c6) as an ionophore inpvc matrix was developed. the influences of membrane composition, selectivity, response time,reversibility and temperature on the electrode performance were investigated. the electrodeshowed a near nernstian response for sn2+ ions over a concentration range from 1.0× 10-6 – 1.0× 10-2 m with a slope of 27...

this paper focuses on the effects of the addition of an ionic liquid, 1-allyl-3-butylimidazilium bis(trifluoromethane sulfonyl)imide ([abim]tfsi), which has a high affinity for benzene, into the poly(vinyl chloride) (pvc) membrane on the pervaporation characteristics of the removal of benzene from aqueous solutions of dilute benzene. when aqueous solutions of 100～500 ppm benzene were permeated ...

corrosion makes huge economic and ecologic damage all over the world. biologic corrosion of sewer pipes is considered as a serious limitation in economic perspectives. to prevent biologic corrosive damage, lining techniques can be applied by materials and aggregate resistant to attack bacterially in sewer pipes. the role of bacteria is that they convert sulfur compounds into sulfuric acid which...

Simultaneous electrospinning of two polymer solutions in a side-by-side fashion is conducted for two bicomponent polymer systems— poly (vinyl chloride)/segmented polyurethane (PVC/Estane) and poly(vinyl chloride)/poly(vinylidiene fluoride) (PVC/PVDF). The new experimental device is described and suitable process conditions to electrospin bicomponent fibers are described. Field emission scanning...

Consideration of needs for public health interventions and new research requires comparative assessments of the health benefits that are likely to result from alternative uses of limited regulatory and technical resources. This paper briefly examines regulatory and research priorities in the light of recent information on the carcinogenic hazards of vinyl chloride and alkyl and vinyl halides re...

In 1974, vinyl chloride (VC) was first reported in the open scientific literature to induce angiosarcoma of the liver both in humans and in animals. Additional research has now demonstrated the carcinogenicity of VC to other organs and at lower concentrations. The target organs for VC now clearly include the liver, brain and the lung, and probably the lymphohematopoietic system. The evidence fo...

The National Institute for Occupational Safety and Health (NIOSH) in early 1974 began industrial hygiene studies of vinyl chloride exposed workers. Three VC monomer plants, three VC polymerization plants, and seven PVC fabrication plants were surveyed. V polymerization plant workers and workers in one job category in VC monomer plants were exposed to average levels above 1 ppm. The highest aver...

Zirconium oxy-salts were hydrolyzed to form positively charged polymer or cluster species in acidic solutions. The zirconium hydrolyzed polymer was found to react with a negatively charged polyelectrolyte, such as poly(vinyl sulfate), and to form a stoichiometric polyion complex. Thus, colloidal titration with poly(vinyl sulfate) was applied to measure the zirconium concentration in an acidic s...