Styrene trimers

Figure 12.3 Clrromatogr-ams of an ignition-resistant high-impact polystyrene sample (a) Microcolumn SEC fi ace (b) capillary GC trace of peak x . Peak identification is as follows 1, ionol 2, benzophenone 3, styrene dimer 4, palmitic acid 5, stearic acid 6, styrene trimers 7, styrene trimer 8, styrene oligomer 9, Irganox 1076 and Irganox 168 10, styrene oligomer 11, nonabromodiphenyl oxide and 12, decabromodiphenyl oxide. Reprinted with permission from Ref. (12).

Figure 3.9 Residual styrene trimer as a function of devolatilizer vacuum. Reprinted with permission from B. J. Meister and A. E. Platt, Ind. Eng. Chem. Res., 28, 1662 (1989). Copyright 1989 American Chemical Society...

Figure 31.6 Effects of styrene monomer (SM) (A), styrene dimers (SD-01, SD-08, SD-09) and styrene trimers (ST-01, ST-02, ST-03) (B) on proliferation of MCF-7 cells [10]. The cells were treated with test compounds for 6 days., p < 0.05, 0.01 (vs control). Each value represents the mean SD (rt = 3 wells)...

PS products contain certain kinds of styrene dimers (SDs), such as 2,4-diphenyl-1-butene and cis- and rraws-l, 2-diphenylcyclobutane, and styrene trimers (STs), such as 2,4,6-triphenyl-1-hexene and l-phenyl-4-(l -phenylethyl)tetralin. The contents of these substances differ with each product. It has also been found that SDs and STs migrate into fatty solvents, such as n-heptane or vegetable oil, but the migration into aqueous solvents is very slight. SDs tend to be affected by the heating time of containers involving solvents, and STs tend to be affected by the length of contact time with containers. 

USB Catalyst in polymerization of acetylene to benzene and styrene, trimerization of ethynyl compds, cyclization of butadiene. 

Nelson [136] has reported studies of zinc, zinc oxide, and zinc borate in coatings on or as a filler in modified polyphenylene oxide (m-PPO). Zinc arc spray, or zinc, zinc borate, and zinc/zinc borate in epoxy coatings showed a substantial reduction of flame spread index (ASTM E-162) (I,) for m-PPO. Zinc oxide in epoxy, however, showed a dramatic increase in I, on m-PPO. Zinc arc spray on m-PPO led to enhanced stability in the 500-600°C range in both isothermal and GC/MS experiments. It was speculated that since zinc melts at 420OC, just at the early stage of decomposition of m-PPO, this could allow intimate contact with the charring substrate. As in pure polystyrene, char formation is enhanced in air in m-PPO, and this was thought to be enhanced further by the presence of zinc. Indeed it was observed that volatilization of small molecules is reduced for m-PPO with zinc present at temperatures under 700°C, with preference for volatilization of the triaryl phosphate flame retardant, styrene trimer, and PPO dimers. 

SS 3-butene-1,3-diyldibenzene (styrene dimer) SSS 5-hexene-1,3,5-triyltribenzene (styrene trimer)... 

SSS CH2=C C6H5)CH2CH2 C6H5) CH2CH2 C6H5) styrene trimer) 312 2493 28.1... 

Wang and Smith [60] applied Py-GC to determine the composition and microstructure of styrene-MMA copolymers. The composition of these copolymers was quantified by monomer peak intensities obtained from pyrolysis. Becanse of the poor stability of MMA oligomers, neither MMA dimers nor trimers were detected nnder normal pyrolysis conditions. The number average sequence length for styrene was determined from pure and hybrid styrene trimer peak intensities. The number average sequence... 

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