Vinyl chloride-styrene-dioctyl

Chem. Descrip. Dioctyl maleate CAS 2915-53-9 EINECS/ELINCS 220-835-6 Uses Comonomer used in polymerization with vinyl acetate, vinyl chloride, styrene and derivs. of acrylic and methacrylic acids used in latex paints, textiles as specialty plasticizer Properties APHA50 max. liq. m.w. 340 sp.gr. 0.939-0.944 vise. 9.1-9.5 cs (100 F) pour pt. -75 F acid no. 0.10 max. flash pt. (COC) 370 F ref. index 1.452-1.454 94% act. 

Thermoreversible gelation, as a consequence of crystallization from dilute solutions of random copolymers has been observed in a variety of mixtures. These include, among others, poly(vinyl chloride) in dioctyl phthalate,(55) poly-(acrylonitrile) in dimethyl formamide,(56) nitrocellulose in ethyl alcohol,(272) methyl cellulose in water,(273) ethylene copolymers,(274) syndiotactic isotactic and atactic poly(styrene),(275-279) and random copolymers of ethylene terephtha-late with isophthalate.(280) Flory and Garrett (281) have shown that the classical thermoreversible gelation system, gelatin in water, is the result of a crystal-liquid transformation. The gelation or dissolution can be treated as a first-order phase transition. 

Figure 3.5 Effect of membrane composition on electrical conductivity and transport number of cation exchange membrane prepared by the paste method. (O, O) transport number ( , ) specific conductivity. DVB divinylbenzene St styrene PVC poly(vinyl chloride). Composition DVB/(St + DVB) — 0.1 (by weight) numbers in the figure are DOP/PVC (DOP dioctyl phthalate -additives) (by weight). The copolymer membrane is sulfonated with concentrated sulfuric acid.

The van der Waals bonds between monomer molecules are replaced by covalent bonds between the monomeric units in polymerization. Since van der Waals bond lengths are about 0.3-0.5 nm and covalent bond lengths are, in contrast, about 0.14-0.19 nm, a general contraction occurs. The contraction increases with decreasing monomer molecule size, since more van der Waals bonds per unit mass must be eliminated. Thus, ethylene contracts by about 66%, vinyl chloride by about 34%, styrene by about 14%, and W-vinyl carbazole by as little as about 7.5%. Polymerization of ethylene oxide leads to a volume contraction of 23%, of tetrahydrofuran to one of about 10%, but that of octamethyl cyclotetrasiloxane, however, to a contraction of only 2%. Some strained bicyclic ring systems even polymerize with an expansion. With polycondensation, the volume contraction is smaller with decreasing size of eliminated residue. Polycondensation of hexamethylene diamine with adipic acid leads to a contraction of 22% (water elimination), that of hexamethylene diamine and dioctyl phthalate, on the other hand, to one of 66% (elimination of octanol). 

Polyfunctional Fatty Acid Esters. Dioctyl sebacate (DOS), dibutyl sebacate (DBS), diisobutyl adipate (DIBA), monoisopropyl citrate, stearyl citrate, triethyl citrate (TEC), butyl and octyl maleates, and fumarates are very important plasticizers for the preparation of stable PVC pastes and of low-temperature-resistant PVC products. DOS is used most often because of its high plasticization efficiency, its low volatility, and its resistance to water and soap solutions. It presents many advantages for PVC products. DBS, DIBA, and monoisopropyl, stearyl, and triethyl citrates are recommended for plastics components intended for packaging of food products. Butyl and octyl maleates and fumarates can be used for internal plasticization, that is, for copolymerization with vinyl chloride, vinyl acetate, and styrene. 

Uses Plasticizer latex paint formulation internal plasticizer for copolymerization with vinyl acetate, vinyl chloride, acrylates, and styrene chemical intermediate for prod, of surfactant, sodium dioctyl sulfosuccinate Regulatory Canada DSL listed... 

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