Poly-l,3-cyclohexadiene

Poly([7,8-bis(trifluoromethyl)tetracyclo [4.2.0.02 8.05 7]octane-3,4-diyl]-1,2-ethenediyl), 3457 Poly[borane(l)], 0134 crs-Poly (butadiene), 1480 Poly(l,3-butadiene peroxide), 1528 Poly(butadiyne), 1382 Poly(carbon monofluoride), 0336 Poly(chlorotrifluoroethylene), 0589 Poly(l,3-cyclohexadiene peroxide), 2380 Poly(cyclopentadienyltitanium dichloride), 1837 Poly(diazidophosphazene), 4781 Poly(dibromosilylene), 0282 Poly(difluorosilylene), 4324 Poly(dihydroxydioxodisilane), 4474 Poly(dimercuryimmonium acetylide), 0665 Poly(dimercuryimmonium azide), 4606 Poly(dimercuryimmonium bromate), 0253 Poly (dimercury immonium iodide hydrate), 4449 Poly (dimercury immonium perchlorate), 4006 Poly(dimercuryimmonium permanganate), 4603 Poly (dime thylketene peroxide), see Poly(peroxyisobutyrolactone), 1531 Poly(dimethylsiloxane), 0918 Poly(disilicon nitride), 4752 Poly(ethenyl nitrate), see Poly(vinyl nitrate), 0760 Poly(ethylene), 0778 Poly(ethylene terephthalate), 3256 Poly(ethylidene peroxide), 0831 Poly(furan-2,5-diyl), 1398 Poly(germanium dihydride), 4409 Poly(germanium monohydride), 4407 Poly(isobutene), 1578 Poly(methyl methacrylate peroxide), 1913... 

Poly(l,3-cyclohexadiene-co-styrene) having a M of 63,603 daltons and containing up to 86% 1,3-cyclohexadiene has been anionically prepared using l,3-bis(l-lithio-l,3,3-trimethyl-butyl)benzene as catalyst. When hydrogenated, the material is converted into a high-performance resin. 

Poly(l,3-cyclohexadiene) homopolymers were previously prepared by Natori [3] using n-BuLi and tetramethylethylenediamine and had excellent thermal and mechanical properties. 

Poly((l,3-cyclohexadiene)-g-maleic anhydride), (I), was prepared by Imaizu-mi [4] by postreacting poly(l,3-cyclohexadiene) with maleic anhydride in 1,2,4-trichlorobenzene. Up to 1.4 wt% maleic anhydride was incorporated using this method. 

Poly((l,3-cyclohexadiene)-co-butadiene), (II), and the hydrogenation product, poly((l,3-cyclohexadiene)-co-butane), (III), were prepared by Nakano [5]. 

Pofy(p-phenylene), 5. This catalyst has been used to polymerize 1,3-butadiene with >97% 1,4-regioselectivity. Attempts to polymerize phenylenes directly results in mixtures of para-, meta-, and orr/io-linked oligomers. In contrast polymerization of cis-5,6-bis(trimethylsilyloxy)-l,3-cyclohexadiene 2 with I in C6H5CI results in exclusive formation of the l,4-poly-l,3-cyclohexadiene 3. This polymer is converted into poly(p-phenylene) (5) by conversion of the trimethylsilyloxy groups to acetyl groups followed by pyrolysis. 

Cassidy PE, Marvel CS, Ray SJ (1965) Preparation and aromatization of poly-l,3-cyclohexadiene and subsequent cross-linking. III. J Polym Sci A3 1553-1564 Cavalca L, Amico ED, Andreoni V (2004) Intrinsic bioremediability of an aromatic hydrocarbon-polluted groundwater diversity of bacterial population and toluene monoxygenase genes. Appl Microbiol Biotechnol 64 576-587... 

Natori I, Natori S, Sato H (2006) Synthesis of soluble polyphenylene homopolymers as polar macromolecules complete dehydrogenation of poly(l,3-cyclohexadiene) with controlled polymer chain structure. Macromolecules 39 3168-3174 Nevin A, Shirley IM (1985) Polymer coatings. EP 163392... 

Lefebvre, G Dawans, F. 1,3-Cyclohexadiene polymers. Part I. Preparation and aromatization of poly-l,3-cyclohexadiene. J. Polym. ScL, Part A 1964, 2, 3277-3295. 

Of all the chemical processes which were reviewed and described in references [1-3], it should be noted that up to now only the Kovacic and Yamamoto reactions and, to a lesser extent, the thermal dehydrogenation of poly(l,3-cyclohexadiene) have been used to synthesize polyphenylenes for usual or special applications. Only recently, a new impulse has been given to the synthesis of linear functionalized high molecular-weight PPPs with the adaptation of the Suzuki reaction, and this is currently one of the best possible ways of synthesizing soluble, functionalized PPPs for specific applications with, in particular, the realization of rigid rod-like polymers for mechanical applications, as will be shown in Section 2.1.3. 

The reaction is based on the aromatization of the soluble poly(l,3-cyclohexadiene) (PCHD) precursor. 

A quite different route was developed by Francois et al. with the view to obtaining soluble block copolymers containing long PPP chains [35,36]. Their method is based on the synthesis of a soluble polystyrene-poly(l,3-cyclohexadiene) precursor (PSt-PCHD) which is first aromatized to a soluble polystyrene (PSt)-PPP block copolymer. In a further thermal treatment the PSt sequences are decomposed, leaving pure PPP films or powders [35a]. 

Allyl nickel complexes yield crystalline poly(l,3-cyclohexadienes) with 90% 1,4-structures and melting points between 180 and 270 °C [425]. Thiourea inclusion templates give polymers with purely 1,4 structures and unusually high melting points, between 370 and 380 °C. Additional polymers of cyclic dienes are listed in Table 22 [331,426-429]. 

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