Copolymer, composition viscosity

An electric conductive rubber base containing carbon black is laminated with an electric conductive cover layer of phosphoric acid ester plasticizer and other ionic surfactants to prepare antistatic mats, where the covers have colors other than black. It is also reported that alkyl acid phosphates act as color stabilizer for rubber. Small amounts of phosphate esters are helpful in restoring reclaimed rubber to a workable viscosity [284,290]. Esters of phosphoric acid are used in the production of UV-stable and flame-retarded alkylbenzenesulfonate copolymer compositions containing aliphatic resins and showing a high-impact strength... 

Very similar variations in average copolymer composition with conversion have recently been observed in the styrene methyl methacrylate system by both Johnson et al ( and by Dionisio and O Driscoll (. The reason for the variation may be due to a viscosity effect on propagation rate constants QO). 

Fig. 12. The relative viscosity of polyacrylamide-co-acrylates versus different copolymer compositions depending on the presence of the low-molecular-weight electrolyte sodium sulfate. All Samples have the same degree and distribution of polymerization...

Kraus et al. (74,75) studied the steady flow and oscillatory flow behavior of linear triblocks of S-B-S and B-S-B and radial block copolymers of the type (B-S-) 3, (S-B-)3, and (S-B-)4. For block copolymers of the same molecular weight and composition, those with end blocks of PS always have higher viscosities. However, when compared with corresponding linear block copolymers, the viscosities of the radial block copolymers are generally lower. 

Fig. 1. Kinetic curves of styrene absorption. Curve 1 viscose staple fibre, curve 2 cotton, curve 3 graft copolymer of viscose staple fibre and polystyrene, composition 86.1% 13.9%, curve 4 graft copolymer of cotton and polystyrene, composition 84.8% 15.2%, curve 5 grafted polystyrene isolated from the copolymer with staple fibre, curve 6 grafted polystyrene isolated from the copolymer with cotton absorption conditions [St] -1%, M-25, emulsifier concentration 0.2%, temperature - 65°...

The relationship between molecular wei t and intrinsic viscosity for each copolymer composition was not established. An approximate value for was (htained from Eq. (1) derived for polyisbbutylene (J9) ... 

With the high-temperature solution polymerization processes, various ethylene homo- and copolymers with different average molecular mass and copolymer compositions are produced. The product portfolio comprises PE-HD, PE-LLD, PE-VLD, and the ethylene/propylene elastomers (EPM, EPDM) (see Figure 2). The thermoplastic products have a wide range of applications [1]. The elastomeric ethylene/propylene copolymers can also be applied widely in the automotive industry, for plastics modification, in industrial applications such as seals, in electrical cables, and in tires [2], Uncured ethylene/propylene copolymers are applicable as viscosity index improvers for lubricant oils [5]. 

Metallocene catalysis is an alternative to the traditional Ziegler-Natta vanadium-based catalysis for commercial polyolefin production, e.g. the use of metallocene-catalyzed ethylene alpha-olefin copolymers as viscosity index modifiers for lubricating oil compositions [23]. The catalyst is an activated metallocene transition metal, usually Ti, Zr or Hf, attached to one or two cyclopentadienyl rings and typically activated by methylaluminoxane. Metallocene catalysis achieves more stereo-regularity and also enables incorporation of higher alpha-olefins and/or other monomers into the polymer backbone. In addition, the low catalyst concentration does not require a cleanup step to remove ash. 

Effects of Copolymer Composition. Figure 3 illustrates the effect of changes in Cg hydrophobe composition on the apparent viscosity versus... 

Copolymers of 2-acrylamide-2-methylpropyldimethylammonium chloride and sodium 2-acrylamide-2-methylpropanesulfonate (AMPDAC-SAMPS) were prepared and their dilute solution properties studied as a function of copolymer composition, temperature, time, pH and added low-molecular-weight electrolytes [39-42]. Equimolar copolymers display a minimal viscosity in pure water and a maximal one in concentrated salt solutions. As the copolymer compositions deviate from an equimolar, charge imbalances increase the hydrodynamic volume of the macromolecules. 

Copolymerization of 18 with styrene and acrylonitrile In the range of 40 to 60 mol % of the metallomonomer the copolymer composition does not depend on the monomeric mixture. The copolymers are soluble in benzene the molecular weights are about 10 Da. Under copolymerization conditions (75 °C, benzene, 1% of the initiator) of 18 with acrylonitrile (25 mol %) a light-yellow product containing -12% vanadium was obtained. The yield was 15%, the product is soluble in DMFA and DMSO, and its intrinsic viscosity was 0.11 (DMSO, 30 °C). IR 1720 (vc=o), 2245 cm (vc n) the ratio of the intensities of the absorptions /(C=0)//(C=N) = 13 1. This method can also be used for the synthesis and polymerization of optically active metallomonomers. 

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