Handbook of Polymer Synthesis Second Edition Episode 15 pdf

... importance of this first example of a solid phase synthesis on polymer support which was followed by the development of numerous polymeric reagents [148]. Presently, the fast expanding technique of combinatorial ... of the great number of hydroxyl groups in the prepolymer, curing with dianhydrides can form very densely crosslinked, second- stage polymers if used in relatively...

Ngày tải lên: 13/08/2014, 16:21

... kind of polymerization is often limited by the occurrence of side reactions, including (1) the attack of the initiator at the carbonyl double bond of the monomer or polymer, (2) chain transfer of ... preparation of ABA block copolymers when bifunctional initiators are used, whereas the first method enables the synthesis of triblock copolymers by addition of the first monomer...

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... University of Technology, Kaunas, Lithuania I. FOREWORD Since 1992 when the first edition of the Handbook of Polymer Synthesis was published a number of new applications for photoconductive polymers ... use of tetrahydrothiophene instead of dimethyl sulphide in the synthesis of the precursor polymer [141]. The use of the cyclic leaving group facilitates the eliminat...

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... is CatÀM 1 polymer þ M 1 À! k 11 CatÀM 1 ÀM 1 polymer ð32Þ CatÀM 1 polymer þ M 2 À! k 12 CatÀM 2 ÀM 1 polymer ð33Þ CatÀM 2 polymer þ M 1 À! k 21 CatÀM 1 ÀM 2 polymer ð34Þ CatÀM 2 polymer þ ... comonomer, as it promotes the polymer s degradability in the presence of light [182]. As a consequence of the diversified nature of the comonomers, a large number of variants of...

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... conditions of radical-induced vinyl polymerization (e.g., the rate of polymerization was found to be proportional to the square root of the initiator concentration). However, the average degree of polymerization ... AIBN-started radical polymerization of o-ClSt in bulk at 30  C. He found the rate of polymerization to be about 15 times higher than that of styrene. Propagation...

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... course of the polymerization [247–249]. Particularly attractive aspects of this technique of radiation polymerization are the excellent efficiency of polymerization together with the high rates of polymerization ... the degree of polymerization should be a function of the number of polymer lattices and initiator con centration. However, for the polymeri- zation of VC in emul...

Ngày tải lên: 13/08/2014, 16:21

... rings: ð64Þ At a polymerization temperature of 22  C, approximately 80% of the cyclopentane rings in the polymer are trans. Table 23 shows some other examples of the polymerization of nonconjugated ... coordination of the monomer occurs with only one double bond for both isomers of pentadiene. In the presence of CrO 3 only the trans-isomer of pentadiene is polymerized to a...

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... Ziegler–Natta polymerization of norbornene (NBE) – received by means of TiCl 4 /EtMgBr catalysts a novel polymer [2,3]. In 1957 Eleuterio (Du Pont) filed a patent, which describes the polymerization of severa ... predictions [267]. These secondary metathesis reactions of course may also affect the microstructure of the polymers, e.g., the fraction of cis double bonds [275,283]. Th...

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... interesting group of polymers. Two precursor routes were recently explored. Firstly, synthesis of PEKs having pendant t-butyl groups [194,214, 215] which can be eliminated as isobutylene, and secondly, ... polycondensations of the monomers (95c,d) [154 ]. ð93Þ ð94Þ ð95Þ 1. Liquid-crystalline PEKs? One research group reported in three papers [155 157 ] on synthesis and characteriza-...

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... respectively. Setting the number of moles of the polyol, n pol ,tobe1,r becomes the number of moles of the chain extender. Number of moles of the diisocyanate, n ISO , at the stoichiometric ratio of NCO/OH groups ... the immiscibility of the hard and soft segments. Degree of phase separation (or phase mixing) affects the properties of the polymers, and it depends on the str...

Ngày tải lên: 13/08/2014, 16:21