Poly isobutylene n

The first synthesis of multiarm star polyisobutylene (PIB), with DPn(arm)=116 and the average number of arms=56, was described by Marsalko et al. [6]. The procedure started with the living polymerization of IB by the 2-chloro-2,4,4-trimethylpentane (TMPCl)/TiCl4 initiating system in CH2Cl2/hexane (50/50 v/v) at -40 °C in the presence of triethylamine. At 95% IB conversion, divinylben-zene (DVB, 6, containing 20% ethyl vinylbenzene) was added to effect linking at r=[DVB]/[TMPCl] = 10. 

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D 2. Delmas, G., D. Patterson, and T. Somcynsky Thermodynamics of poly-isobutylene-n-alkane systems. J. Polymer ScL 57, 79 (1962). 

Fig. 1.4 gives such a plot, which was prepared by Philippoff (8,9) from his early measurements on a 15 per cent solution of polyisobutylene (P-100) in decalin (measurement temperatures 30 and 50°C). From this figure it is clearly seen that An as a function of p21 is non-linear. In contrast to the above mentioned solution of S 111 in methyl 4-bromo-phenyl carbinol, the solution of the poly-isobutylene P-100 in decalin does not form a second order fluid. However, for the product A n sin 2%, one obtains a beautiful straight line. The stress-optical law seems to hold also for this more general type of fluid. ... 

SBR etc., yet it has been covulcanized with those rubbers to provide useful materials (4). In this work, we have found that poly(isobutylene-co-P >inene) with 10 mole% unsaturation can also be cocured with a high cis- l,4-p<%lHit ene rubber. Covulcanization has been demonstrated by an experiment in which poly(isobutylene-co- -pinene) phis cis-l,4.polybutadiene were mixed cm a laboratory mill for 40 minutes, cured (30 minutes at 160°) and the vulcanizate extracted with n-hexane (24 hours at 65°). The fact that the amount of extractables was 2% indicates a measure of co-vulcanization. The covulcanizate exhibited a tensile strength of 175 kg/cm and elongation at break of 300%. 

Poly isobutylene. 9. A, 3-bromo-4-methoxy toluene B, < -methoxy benzyl bromide C, < -bromophenetole. 15. M, (CH2=CH)20 N, CICH2CHOHCH2OCH3, retention ... 

Table I. Flow rate dependence of tg and Fj determined at 100 C for several n-alkanes on a poly-isobutylene column...

Cairns and Neustadter (1975) studied the stability of carbon dispersions stabilized by BP 45, a copolymer of methacrylic esters for which R in the ester group -COOR could be the straight chain C4 or Cg-iz alkyl groups, or the amino substituted ethyl group -CH2CH2NH2. They also studied the stabilizer PV30-TEPA, a succinimide terminated poly(isobutylene). Flocculation was induced by the addition of ethanol to the dispersion medium, which was n-heptane. Their results, which compare the CFVs with the 0-compositions determined by the method of Comet and van Ballegooijen (1966), are presented in Table 9.1. 

Figure 2-17 shows that as data on narrow-distribution polystyrene in benzene (25, 30°C), methyl ethyl ketone (35°C), and cyclohexane (different temperatures above ) obey criterion A (i). Here, M denotes M/aMt and benzene at 25°C is chosen as the reference state S. The data points in Figure 2-18 have been obtained by shifting horizontally the data for poly(isobutylene) fractions in cyclohexane (25°C), n-heptane (25°C), and isoamyl isovalerate (lAIV) (different temperatures above 9) until they matched the master curve of as for polystyrene. The good matching is consistent with criterion A (ii). 

Figure 2-19 displays logo, plotted against logM for polystyrene in the same three solvents as in Figure 2-17. Apparently, these data do not conform to criterion B (i). It was found that the data for poly (isobutylene) in isoamyl isovalerate, n-heptane, and cyclohexane exhibited a similar breakdown of criterion B (i) [49]. However, we have to remark that the master curves of a,...

Normal stress measurements for some MLC nematics was reported to be consistent with that of a second-order fluid, that the low frequency limit of G /co equaled the low shear limit of N /(dy/dty [36]. Coleman and Markowitz demonstrated that for a second-order fluid in slow Couette flow, the viscoelastic contribution to the normal thrust must have a sign opposite to the inertial contribution on thermodynamic grounds [37]. A textbook by Walters stated that the measurements of first normal stress difference have invariably led to a positive quantity except for one case which was later found to be in error [38]. Adams and Lodge reported the possible observation of a negative value for Nj for solutions of poly isobutylene + decalin [39]. This result was obtained by a combination of obtained from radial... 

Oppanol B n. Poly(isobutylene), manufactured by BASF, Germany. 

Poly(isobutylene co-isoprene) n. Poly(2-methyl-1 -propene-co-2-methyl-1,3-butadiene). 

Vapor-liquid equilibrium data of poly(isobutylene) in n-pentane and n-heptadecane... 

Vapor-Kquid equilibrium data of poly(isobutylene) in n-pentane and n-heptadecane Data extract from Landolt-Bornstein VIII/6D3 Polymers, Polymer Solutions, Physical Properties and their Relations I (Thermodynamic Properties Equilibria of Ternary Polymer Solutions) ... 

High pressure fluid phase equilibrium data of poly (isobutylene) in carbon dioxide and n-heptane... 

LB Number Substance 1 CAS Number 1 Substance 2 CAS Number 2 Substance 3 CAS Number 4 151 poly(isobutylene) 9003-27-4 carbon dioxide 124-38-9 n-heptane 142-82-5 ... 

Table 1 Coexistence data (cloud points (LCST behavior)) of poly(isobutylene) (M /(g/mol) Mw/(g/mol) = 1000000) in carbon dioxide (CO2) and n-heptane (C7H16) [2002JOU1]. = 600000,...

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