Oligomeric plasticizers

This suggests a physical rather than a chemical mechanism of the phenomenon concerned. Thus, the high values of tg 6 in foams are not only due to the presence of considerable amounts of water but also to a secondary phenomenon - interphase polarization resulting in additional dielectric losses, which are many times higher than in monolithic oligomeric plastics. 

Berlin, A, A., Shutov, F. A. Strengthened Gas-Filled Plastics. Moscow Khimiya 1980 (Russ.) Berlin, A. A., Shutov, F. A. Morphology of Oligomeric Plastic Foams, in Physico-Chemistry and Chemistry of Reactive Oligomers. Alma-Ata AN Kaz. SSR Publication 1979, pp. 50 (Russ.)... 

Table 5.2 Solubility parameters of monomeric and oligomeric plasticizers.

Two oligomeric plasticizers, one trimer (TbC-3) and one heptamer (TbC-7), are prepared by transesterification of TbC and DEG The tertiary hydroxyl group on TbC seems to have participated in the reaction, causing uncontrolled branching as shown in Fig. 4.39. 

Polymeric or oligomeric plasticizers are advantageous due to their inherent low volatility. Therefore, they have been suggested as replacement materials for traditional plasticizers. 

The alkoxy titanate compounds formed by reaction of one mole of tetraalkyl titanate with one mole of a dialkanolamine are excellent esterification catalysts for the manufacture of phthalate-based plasticizers (112). If a 1 1 molar mixture of alkanolamine and water is used ia place of the alkanolamine, oligomeric titanate complexes are formed, which have high catalyst activity and can be used as thixotropic additives to paints and other aqueous coating formulations (113). 

An EB-curable struetural adhesive formulation usually eonsists of one or more crosslinkable oligomeric resins or prepolymers, along with such additives as reactive diluents, plasticizers, and wetting agents. The oligomer is an important component in terms of the development of mechanical properties. The adhesive and cohesive properties depend on the crosslink density, chemical group substitution, and molecular organization within the polymer matrix. Adhesion is achieved... 

Linear alcohols (C12-C26) are important chemicals for producing various compounds such as plasticizers, detergents, and solvents. The production of linear alcohols by the hydroformylation (Oxo reaction) of alpha olefins followed by hydrogenation is discussed in Chapter 5. They are also produced by the oligomerization of ethylene using aluminum alkyls (Ziegler catalysts). 

Ljungberg, N., Colombini, D. and Wesslen, B. 2005. Plasticization of polyjlactic add) with oligomeric malonate esteramides dynamic mechanical and thermal film properties. Journal of Applied Polymer Science 96 992-1002. 

A more recent raw material for plasticizer alcohols is crack-C4 as a byproduct of steamcrackers in ethene/propene production. After extraction of butadiene for use and etherification of isobutene with methanol to methyl-tertiary-butylether MTBE as an octane enhancer, a stream is left containing 1-butene, 2-butene, and butanes, so-called raffinate II. Oligomerization of the butenes yields C8 olefin mixtures ( dibutene ) as the main product and the corresponding C12 olefins as the main byproduct (tributene). They are the... 

The development of plasticizers has been plagued with toxicity problems. Thus the use of highly toxic polychlorinated biphenyls (PCBs) has been discontinued. Blood stored in plasticized PVC blood bags and tubing may extract phthalic add esters, such as DOP. These aromatic esters are also distilled slowly from PVC upholstery in closed automobiles in hot weather. These problems have been solved by using oligomeric polyesters as nonfugitive plasticizers instead of DOP. 

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