Poly-2,3-dimethylbutadiene

Table 20. Influence of Pressure and Initiator Concentration upon the Microstructure of Poly-2,3-dimethylbutadiene [monomer] = 3.75 molar...

The formation of cyclic peroxides has been proposed (14) in the oxidation of poly (2,3-dimethylbutadiene). The same reaction in cts-1,4-polybutadiene would also yield additional allyloxy radicals. 

The pyrolysis products of 1,3-diene-sulfur dioxide copolymers were analyzed in a field-ion mass spectrometer and the fragmentation results suggest an alternating 1 1 copolymer for poly(butadiene sulfone), poly(isoprene sulfone) and poly(2,3-dimethylbutadiene sulfone) [48]. 

Methyl rubber Poly(2,3-dimethylbutadiene) Bayer, Germany (World War I)... 

Chemists at Leverkusen were familiar with cellulose ester plastics and poly 2,3-dimethylbutadiene rubber, but these were produced on a small scale without the benefit of a knowledge of macromolecular chemistry. The production of Buna S, which was a copolymer of butadiene and styrene, which was aa laboratory curiosity. In spite of opposition from influential members of Ae board of directors of I.G. Farben-industrie, Bayer directed the development of a process for the production of styrene monomer and polystyrene at the Ludwigshafen and Bitterfield plants. 

We have prepared pure 1,4-poly(2,3-dimethylbutadiene) (PDMB) by polymerizing DMB with aluminum alkyl/TiCli, initiator systems (11,16,46). When the Al/Ti ratio was 2 1 and the amount of the initiator systems to the DMB was carefully adjusted, pure 1,4-cis PDMB was obtained, but when the Al/Ti ratio was 1 2, pure 1,4-trans PDMB was obtained. From the NMR analysis we concluded, (especially after spiking with the model compound, 2,3,3-trimethyl-... 

Two experimental investigations of head-to-head, tail-to-tail polypropylene, obtained by reduction of poly(2,3-dimethylbutadiene), give discordant results [17,18]. Values of 4.5 and 6.1-6.4, respectively, are obtained for the characteristic ratio, C , of samples of high molecular weight. 

In this paper we wish to report the hydrogenation of cis-1,4-polybutadiene, cis-l,4-polyisoprene, cis-l,4-poly(2,3-dimethylbutadiene), and trans-l,4-poly(2,4-hexadiene) which were prepared with lanthanide polymerization catalysts. The physical and mechanical properties of these hydrogenated polymers are discussed. 

This is also found in hydrogenated poly-2,3-dimethylbutadiene, used as a model compound and in alternating copolymers of ethylene and butane-2 [2], In the polypropylenes examined by van Schooten and Mostert [3] and in ethylene-propylene copolymers, they found an absorption band near 9.0 pm, although, unlike van Schooten and Mostert [3] (see above), it was much less sharp than the model compound. 

All spectra containing the 13.3-pm peak show a further small band at 10.9 pm, which is also found in the spectrum of poly-2,3-dimethylbutadiene. To summarise, the IR spectrum of amorphous polypropylene prepared using vanadyl catalysts in addition to normal head-to-tail structures -CHCH3- CH2-CH CH3-CH2- shows the following features ... 

All ethylene propylene and polypropylene polymers showing an absorbance at 13.3 pm also show small absorbance at 10.9 pm, which is also found in poly 2,3-dimethylbutadiene. 

Poly(l,l-dimethylallyl alcohol-alt-MA), 311 Poly(dimethylaminophenyl acetylene-co-MA), 335 Poly(2,3-dimethylbutadiene-alt-MA), 345, 346,... 

DRS was used to study the dynamics of hydrogen-bonded polymer blends of poly(2,3 dimethylbutadiene (DMB) [86%]-co-hexafluoro-2-hydroxyl-2-propyl)styrene (HFS) [14%]) copolymer with PVME [42]. The copolymer was capable of forming strong intermolecular hydrogen bonds, while minimizing the degree of intramolecular association, and its blends with PVME were miscible over the entire... 

Poly(ester) resin, rigid (ca. 50% styrene) Poly((A -2-methoxyethyl)methacrylamide) Poly(2,3-dimethylbutadiene) (methyl rubber)... 

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