100-42-1 m-Methylstyrene

Reported vapor pressures of m-methylstyrene at various temperatures and the coefficients for the vapor pressure equations... 

FIGURE 3.1.1.39.1 Logarithm of vapor pressure versus reciprocal temperature for m-methylstyrene. 

Mesomorphic forms characterized by conformationally ordered polymer chains packed in lattices with different kinds of lateral disorder have been described for various isotactic and syndiotactic polymers. For instance, for iPP,706 sPP,201 sPS,202 syndiotactic poly(p-methylstyrene) (sPPMS),203 and syndiotactic poly(m -methylstyrene),204 mesomorphic forms have been found. In all of these cases the X-ray fiber diffraction patterns show diffraction confined in well-defined layer lines, indicating order in the conformation of the chains, but broad reflections and diffuse haloes on the equator and on the other layer lines, indicating the presence of disorder in the arrangement of the chain axes as well as the absence of long-range lateral correlations between the chains. 

Each set of experiments was carried out under the same reaction condition except using different comonomers, i.e. p-methylstyrene, o-methylstyrene, m-methylstyrene and styrene, respectively. The compositions of copolymers were determined by H NMR spectra, and the thermal properties (melting point and crystallinity) were obtained by DSC measurements. Overall, all comonomers show no retardation to the catalyst activity. In fact, the significantly higher catalyst activities were observed in all copolymerization reactions (runs 2-5), comparing with that of ethylene homopolymerization (run 1). Within each set (runs 2-5 and 6-9) of comparative experiments, p-methylstyrene consistently shows better incorporation than the rest of comonomers, i.e. o-methylstyrene, m-methylstyrene and styrene. Both catalysts with constrained mono- and di-cyclopentadienyl ligands are very effective to incorporate p-methylstyrene into polyethylene backbone. In runs 2 and 6, more than 80 % of p-methylstyrene were converted to copolymer within one hour under constant (- 45 psi) ethylene pressure. On the other hand, only less than half of styrenes (runs 5 and 9) were incorporated into ethylene copolymers under the same reaction conditions. The significantly... 

S. Nozakura, T. Kitazawa, Y. Yasuhara, and S. Murahashi Infrared absorption bands possibly associated with the helical structure of polystyrene, poly-p-methylstyrene, and poly-m-methylstyrene prepared with Ziegler catalyst. Bull. chem. Soc. Japan 32, 313—314 (1959). 

Figure 9. Helix structure (a) side and end view of the chain of poly-m-methylstyrene (21) (b) side and end views of the macromolecule of isotactic crystalline poly-i-propyl vinyl ether (22)...

PMMA P(MAA VAC) PmMS PMP PMTFPS polylmethyl methacrylate) polylmethylacrylic acid-co-vinyl acetate) poly(m-methylstyrene) poly(4-methyl-1 -pentene) poly(methyKtrifluoropropyl)siloxane)... 

C8H16 1-methyl-1-ethylcyclopentane 16747-50-5 1.099E-K10 81.820 16513 C9H10 m-methylstyrene 100-80-1 9.660E+09 77.400... 

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