Handbook of Polymer Synthesis Second Edition Episode 16 pps

... homopolymers than those of the copolymers. Crosslinking with peroxides increases the impact and tensile strength of PCL and PLA copolymers [31–33]. Micromonomers were prepared from ring opening polymerization ... polymerization of cyclic ester with functionalized initiator (3). Synthesis of polycaprolactone micromonomer. ð3Þ Table 1 Copolyesters of L-lactic acid (LLA) and e-hydrox...

Ngày tải lên: 13/08/2014, 16:21

... non-curable polymers containing pendant imide rings have been synthesized and studied with the objective of improving the properties of classical addition polymers [234–237]. The synthesis of these polymers ... 300  C, isomerization of the as-prepared endo norbornenyl isomer takes place, then a retro Diels–Alder process occurs with evolution of cyclopentadiene, and then polymeriz...

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... toluene and amorphous polymers during homogeneous polymerization in tetrahydrofuran. The softening points of the crystalline polymers were about 240  C [342]. Atactic polymer of t-butyl vinyl ketone ... rate of polymerization of crotonaldehyde increases with the dielectric constant of the solvent is evidence for an ionic mechanism of the polymerization. An increase in dielectri...

Ngày tải lên: 13/08/2014, 16:21

... 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 ... of phenol and acetone by the cumene oxidation process. The polymerizat ion characteristics of a-methylstyrene are considerably different from those of styrene. Wherea...

Ngày tải lên: 13/08/2014, 16:21

... 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

... 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...

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 ... [159] (16) W(CH-t-Bu)(O)(OAr) 2 (PMe 3 )Ar¼ 2,6-Ph 2 -C 6 H 3 [162 ] (17) Ar ¼ 2,6-i-Pr 2 -C 6 H 3 , etc. R 1 ¼ CMe 2 Ph; t-Bu, etc. [163 ,164 ,165 ] (18) R 2 ¼ t-Bu, etc. A...

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... liquid-crystalline character of these PEKs is doubtful. Copyright 2005 by Marcel Dekker. All Rights Reserved. 166 Þ 167 Þ 168 Þ 169 Þ ð170Þ Finally, syntheses of poly(arylene ether)s by modification of precursors ... variety of diphenols by means of sodium carbonate in DMAc. The second strategy is characterized by the preparation of PESs having pendant trifluoromethyl groups b...

Ngày tải lên: 13/08/2014, 16:21