Cycloaliphatic polymers

Cyclopolymerisation leading to polymers with monocyclic units in the main chain proceeds in two steps the first step involves a 1,2-insertion of the coordinated a, ffl-diolefin via one olefinic bond, and the second step, which is a ringclosing reaction, involves an intramolecular insertion of the other olefinic bond undergoing coordination scheme (89) presents both steps for 1,5-hexadiene cyclopolymerisation leading to a cycloaliphatic polymer with poly(methylene-1,3-cyclopentane) structural units [30,450,497] ... 

In the case of the formation of a cycloaliphatic polymer with bicyclic units in the main chain, such as the polymer with poly[methylene-l,3-(2,5-methanocy-clohexane)] structural units obtained in the cyclopolymerisation of 3-vinyl-1,5-hexadiene, the intramolecular insertion, analogous to that presented in scheme (89), is followed by another intramolecular insertion involving a vinyl substituting group ... 

Cycloaliphatic polymers such as poly(methylene-l,3-cykloalkane)s... 

The microstructure of the discussed cycloaliphatic polymers concerns the cis-trans geometrical isomerism of the rings and the relative stereochemistry between the rings. A modified Bovey m-r nomenclature [507] provides a useful description of the microstructure of poly(methylene-l,3-cycloalkane)s, where capital letters (M for mesogenic, R for racemic) denote the stereochemistry of the rings and lower case letters ( m and r) denote the relative stereochemistry between the rings [503], Therefore, cA-isotactic, tram-isotactic, cA-syndiotactic and tram-syndiotactic cyclopolymers may be formed. As in many other cases, 13C NMR spectroscopy reveals information about both the tacticity of the polymer and the ratio of cis to treins rings. 

The symmetry properties of cycloaliphatic polymers are such that polymers with certain microstructures, e.g. tram-isotactic poly (methylene-1,3-cyclopen-tane), are chiral therefore, the cyclopolymerisation of a, trans selective catalysts of C2 symmetry, such as methylaluminoxane-activated resolved (li )-(Thind CH2)2Zr l,l -bi-2-naphtholate, yielded optically active tram-isotactic poly(-methylene-1,3-cyclopentane). The cyclopolymerisation with the (15) enantiomer of the catalyst gave an enantiomeric polymer [505], On the basis of analysis of 13C NMR spectra, the degree of enantioface selectivity for this cyclopolymerisation was estimated to be of 91% [503,505]. 

Cycloaliphatic Polymers via Late Transition Metal Catalysis... 

This extensive section deals with the late transition metal-catalyzed homopoiymerization of cyclic olefins to afford cycloaliphatic polymers, or saturated polymers in which the cyclic structure of the monomer remains intact in the polymer backbone. 

I 4 Cycloaliphatic Polymers via Late Transition Metal Catalysis Ni(O2CR)2 + 9 BFj EtsO + lOAlEt,... 

Adapting the above-mentioned precedents in norbornene polymerization chemistry, the University of Texas research team was able to synthesize cycloaliphatic polymers with pendant-free carboxylic acid groups and carboxylic acids protected with acid-cleaveable groups, such as tert-hvAy esters tailored for 193-nm resist use. They polymerized norbornyl derivatives such as CBN and... 

In Waymouth s route to cycloaliphatic polymers [119-121], the stereoselective cyclopol)onerization of 1,5-hexadiene produces a variety of cycloaliphatic stereoisomers, including optically active pol)oners when using optically active metallocene catalysts [122]. 

Goodall BL (2003) Cycloaliphatic polymers via late transition metal catalysis. In Rieger B, Baugh LS, Kacker S, Striegler S (eds) Late transition metal polymerization catalysis. Wiley-VCH, Weinheim, p 101... 

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