Phenyl siloxane

Figure 9.17 Plot of log [i ]M versus retention volume for various polymers, showing how different systems are represented by a single calibration curve when data are represented in this manner. The polymers used include linear and branched polystyrene, poly(methyl methacrylate), poly(vinyl chloride), poly(phenyl siloxane), polybutadiene, and branched, block, and graft copolymers of styrene and methyl methacrylate. [From Z. Grubisec, P. Rempp, and H. Benoit, Polym. Lett. 5 753 (1967), used with permission of Wiley.]...

An example of the use of silica gel to separate the products from a phenyl siloxane polymerization employing a high efficiency column... 

The aim of this work was to find out how to get more information about stereochemistry and molecular motion of polymer methyl- and methyl-phenyl-siloxanes by measuring longitudinal relaxation times, Tj, and nuclear Overhauser effects, NOE, of the individual building blocks. 

Poly vinyl chloride v Graft(copolymer) PS/PMMA Poly (phenyl siloxane)... 

For example, a,co-bis(trimethylsiloxy)dimethyl(methyldichloro-phenyl)siloxanes can be obtained by the hydrolytic cocondensation of trimethylchlorosilane, dimethyldichlorosilane and methyldichloro-phenyldichlorosilane with subsequent partial polycondensation (CH3)3Si-[OSi(CH3)2]n-[OSi(CH3)(C6H3CI2]m-OSi(CH3)3... 

Preparation of branched oligomethyl(phenyl)siloxanes with metacrylethoxyl groups in the lateral chain... 

Below let us use poly [4-[2-(hydroxyphenyl)propyl-2]-phenyl]phenyl siloxane as an example and illustrate the production of polyphenylsiloxanes from trialkoxyphenylsilane (in our case tributoxy-phenylsilane) synthesised by the second technique, the etherification of phenyltrichlorosilane. The production comprises the following main stages the synthesis of tributoxyphenylsilane and its partial hydrolytic condensation the re-etherification of polybutoxyphenylsiloxane with diphenylolpropane. 

The production diagram of poly [4-[2-(hydroxyphenyl)propyl-2]-phenyl]phenyl siloxane is given in Fig. 67. 

Fig. 67. Production diagram of poly [4-[2-(hydroxyphenyl)propyl-2]-phenyl]phenyl siloxane 1 - etherificator 2, 3, 7 - batch boxers 4, 9 - coolers 5 -nutsch filter 6 - distillation tank 8 - reactor 10 - receptacle 11 - collector...

Fig. 710. Semicontinuous production diagram of polydimethyl(phenyl)siloxane varnish 1 -4, 6, 16 - batch boxes 5 - agitator 7 - heater 8 - hydrolyser 9, 11- hydroejectors 10, 13 - separators 12 - flusher 14, 18 - collectors 15 - polycondensation apparatuses 17 - cooler 19, 20 - settling boxes 21 - ultracentrifuge 22 -container...

Fig. 12. Production diagram of polymethyl(phenyl)siloxanes with active hydrogen atoms and vinyl groups at the silicon atom 1 - 7, 9 - batch boxes 8, 17 - mixers 10 - hydrolyser 11, 15 - collectors 12 - nutsch filter 13 - vacuum distillation tank 14 - cooler 16 - settling box...

Column length 30 m, internal diameter 0.25 mm, film thickness 0.25 xm - Stationary phase 95 % dimethyl, 5 % phenyl-siloxane... 

The NMR data presented above reveal a dynamic heterogeneity of filled PDMS in the frequency range from about 10 kHz to 100 MHz. To determine whether the heterogeneity remains at lower fi equencies, dynamic mechanical measurements are performed. The results for cured, unfilled silicon rubber are compared with those for filled samples containing different fraction of hydrophilic Aerosil (380 m g ). For a more straightforward analysis of the mechanical experiments, a random poly(dimethyl/methyl-phenyl) siloxane copolymer containing approximately 90 mol% dimethyl- and 10 mol% methylphenyl-siloxane units has been used for sample preparation. This copolymer is fully amorphous over the whole temperature range. The results of torsion experiments at a frequency of 1.6 Hz are shown as a function of temperature in Fig. 7. 

Fig. 6.1.4. Room temperature NMR of H in (top) poly(methyl phenyl siloxane), (middle), a polystyrene, poly(methyl phenyl siloxane) (PS-b-PMPS) block copolymer, and (bottom) polystyrene, under single-pulse excitation and magic-angle spinning (MAS). The PMPS is sufficiently mobile that in the pure polymer, and in some samples of the block copolymer, anisotropic molecular motion, when combined with MAS at 4 kHz severely attenuates both dipolar broadening and shielding anisotropy [31].

The diastereoisomers that are thus obtained are separated using GC on a semicapillary column using a polymethyl phenyl siloxane phase. 

Mixtures of methylchlorosilanes produced in the reaction of methyl chloride with silicon copper alloys separate well on a column of FS-16 (Dow DC methyl p-chloro-phenyl siloxane polymer) on firebrick at 70 °C using nitrogen carrier gas396. 

Siloxane-methylphenyl, PMPhS see PMPS (Polymethyl-phenyl siloxane... 

C2H60Si-C7H80Si (dimethyl-siloxane)-(methyl-phenyl-siloxane) copolymer 391... 

Figure 9-19. A universal gel-permeation chromatography calibration curve obtained from measurements on linear poly(styrene) (O), comb-branched poly(styrene) (O ), star-branched poly(styrene) ( ), poly(methyl methacrylate) ( ), poly(vinyl chloride) (a) c -l,4-poly-(butadiene) (A), poly(styrene)-poly(methyl methacrylate) block copolymer (Qj ), random copolymer from styrene and methyl methacrylate O), and ladder polymers of poly(phenyl siloxanes) ( ) (according to Z. Grubisic, P. Rempp, and H. Benoit).

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