Molecular weight of the starting material

The rate and/or the degree of hydrolysis of PVAc is independent of the molecular weight of the starting material. 

However, substantial amounts of the unsubstituted aromatics were found, as shown in Figure 13. At 900°C more than 60 percent of each liquid product was unsubstituted aromatics. The amounts of one, two, and three ring molecules (i.e., benzene, naphthalene, and phenenthrene) varied with the molecular weight of the starting material. For example, the liquid product of MD-3 at 900°C was more than 50 percent benzene while naphthalene was more than 30 percent of the liquid product from MD-4 at 900°C. These unsubstituted aromatics are more thermally stable than substituted aromatic molecules and can be considered soot precursors in staged combustion processes. 

Raw silicone rubber consists of cross-linked macromolecules in a highly viscous liquid state upon vulcanisation it is converted into an elastic rubber. There are hot and cold vulcanisation processes, which employ different starting materials and have different products. The molecular weight of the starting materials for hot vulcanisation is high 300000-1000000. Those for cold vulcanisation are much smaller, 10000-100000. 

Cblorina.ted Pa.ra.ffins, The term chlotinated paraffins covers a variety of compositions. The prime variables are molecular weight of the starting paraffin and the chlorine content of the final product. Typical products contain from 12—24 carbons and from 40—70 wt % chlorine. Liquid chlotinated paraffins are used as plasticizers (qv) and flame retardants ia paint (qv) and PVC formulations. The soHd materials are used as additive flame retardants ia a variety of thermoplastics. In this use, they are combiaed with antimony oxide which acts as a synergist. Thermal stabilizers, such as those used ia PVC (see vinyl polymers), must be used to overcome the inherent thermal iastabiUty. 

When poly(vinyl acetate) was hydrolyzed, and the product treated with periodic acid and then re-acetylated, there was obtained poly(vinyI acetate) of lower molecular weight than the starting material. What does this indicate about the structure of the original polymer About the polymerization process ... 

U- ] glucose into compounds 3, 4, and 5 released upon irradiation 16, 92 and 12% of the radioactivity (Table I, Experiment 2), respectively. The unreleased products appear to be of higher molecular weight than the starting materials (5). In general, insoluble acceptor-polymers are very useful for the determination of the extent of transfer and the study of... 

The degree of polymerization is dictated by the ratio of Hquid resin (cmde DGEBPA) to bisphenol A an excess of the former provides epoxy terminal groups. The actual molecular weights attained depend on the purity of the starting material. Reactive monofunctional groups act as chain terrninators. 

Using benzene as starting material the yield of maleic acid anhydride is about 70 mol %. Using n-C4 hydrocarbons only about 50 mol % yield is obtained. But due to the lower molecular weights of the C4 olefins the wt % values are about 90% in both cases. 

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