Long-chain branching commercial applications

TABLE 30 Influence of Long-Chain Branching in the Polymer on Many Molding Characteristics in Diverse Commercial Applications... 

As discussed above with Chevron-Phillips metallocene-based catalyst which is activated with solid acid catalyst supports, the introduction of low levels of long-chain branching is an important structural feature of polyethylene manufactured for commercial applications with single-site catalysts. Dow s CGC system is able to incorporate low levels of long-chain branching into the polyethylene due to the high level of vinyl-terminated polymer molecules, the relatively high polymerization temperature that is... 

Abstract Thousands of polymeric materials have been made into synthetic polymers, based on a linear structure, and used in commercial applications. The study of synthetic polymeric materials has focused on those derived from long chain linear molecules. Alternatively, cyclic polymers (also referred to as polymer rings or macrocycles) can be prepared, which not only can be branched or cross-linked, but can also form nonco-valently linked structures based on their loop topology. Through a number of different approaches and advances in cyclization techniques, a wide range of novel cyclic polymers have been synthesized in good yields. This review will focus on a variety of synthetic methods and some properties of cyclic polymers using many polymerization mechanisms in various fields of polymer synthesis. 

Poly(dimethylsiloxanes) (PDMS) based on the repeat unit [(CH3)2SiO] are important commercial polymers witii a wide range of applications, for example as adhesives, surfactants, lubricants, sealants, release agents etc. The polymers may be linear, branched or cross-linked into network structures when based on long chain molecules (see Figure 2). 

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