Polymeri zation

In the solid state, the phase matched second harmonic signal increases with increased polymeri zation(7 ). Figure 14 shows preliminary data for the second harmonic intensity of NTDA microcrystals polymerized under x-ray radiation. As the polymer forms, the second harmonic intensity... 

Pectic material Derivative studieda Method Molecular weight Degree of polymeri- zation Fric- tional ratio (f/fo) Refer- ence... 

CBHB)2Ti [1271-29-0] Ti(II) Cp2 dark green 200 pyrophoric catalyst for polymeri-zation of olefins and acetylenes... 

Analogous results have been obtained when operating under such conditions (low conversion, low pressure, etc.) as to guarantee a strictly kinetic control of polymeri-zation -i >-i ). 

A specialty class of carboxyl containing elastomers are the telechelic ionomers. In these systems the carboxyl functionality terminates both ends of the polymer chain. Such polymers range in molecular weight from 1500 to about 6000. These materials can be prepared via several synthetic routes involving anionic or free radical initiated polymeri-zation(32-34). Recently, telechelic sulfonate ionomers of poly-isobutylene have been synthesized(35). These systems offer an unusual opportunity to assess the influence of chain length, chain architecture, cation type, and the Influence of polar additives on ionomer properties. 

Potassium Metaphosphate. Potassium Kurrol s salt potassium polymetaphosphate potassium polyphosphate. (KPOj),. High mol wt polymer degree of polymeri -zation dependent upon preparative conditions. Prepd by dehydration of KHjP04 Pfansteil, ller, J. Am. Chem Soc. 74, 6059 (1952). Structural studies lost, Acta Cryst. 16, 623 (1963) Jost, Schulze, ibid. 25B, 1110 (1969) eidem. ibid. 27B, 1345 (1971). Reviews of metaphosphates J. R. Van Wazer, Phosphorus and its Compounds vol I (Intersdence. New York, 1958) pp 601-678 Thilo, Advan. Inorg. Chem. Radiochem. 4, 1-75 (1962). 

A variety of techniques have been used to monitor the course of the polymeri zation of diallyl o-phtfaalate. The traditional methods of precipitating the polymer from the pol)mierizing solutions lend themselves only to that portion of the process in which gelation has not yet taken place. Methods of studying postgelation kinetics are few. Generally such studies are made on bulk polymers. Starkweather and Eirich [89] determined the refiactive index of the crosslinked polymer by floating cylindrical samples on solvent mixtures which were adjusted imtil the composition had the same refiactive index as the polymer. Then flie refiactive index of solution was measured with an Abbe... 

However, pol3nnerization through the alkene group is the dominant reaction. 1,4-Polymeri-zation also occurs ... 

Bacterial plastics Biosynthesized monomers Polymeri- zation approach M xlO W Poly- dispersity T .ec) r (°c) 7 Mechanical properties Young s Elongation Tensile modulus at break strength (MPa) (%) (MPa) References... 

The ambient temperature vapor deposition polymerization of butadiyne appears to involve an initial impregnation of the substrate film by the butadiyne monomer followed by its polymeri zation When a relatively thick (10 mil) teflon film on which polybutadiyne has been deposited is cut and the cross-section... 

The surface area, average particle size, marber of polymeri -zation sites and number of soap micelles were calculated for each time interval. 

H NMR spechoscopy was used by Grignard et al. [175] to prove the controlled features of the RAFT (co)polymeri-zation of 17/,17/,27/,27/-heptadecafluorodecyl acrylate (ACS) with 2-hydroxyethyl acrylate (HEA). Monomer conversion, polymer molecular weight, and the copolymer composition (in the case of the random copolymers) versus time were determined by H NMR analysis of the polymerization medium. The livingness of the PAC8 chains was confirmed by the synthesis of PAC8-(i-PHEA diblock copolymers. 

Note An example is the metal-catalyzed polymeri zation of hexa-1,5-diene to form poly(buta-... 

Akbulut, U., Toppare, L., Usanmaz,A., Onal,A., Electroinitiated Cationic Polymery-zation of Some Epoksides, MakromoL Chem. Rapid. Commun., 1983,4,259. 

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