P-t-Butylstyrene

Preliminary data does indicate that for a copolymer of similar composition the p(t-butylstyrene) polymer has smaller domains and, in general, a partially phase mixed surface and solid state structure. 

The results of this work are not limited to just S-b-MM and S-b-tBM, but may be extended to include styrene derivatives such as p-methylstyrene and p-t-butylstyrene 1). In addition to t-butyl methacrylate, other alkyl esters capable of stabilizing a carbonium ion, such as benzyl methacrylate and allyl methacrylate, should exhibit similar reactivity toward acidic hydrolysis and TMSI. In contrasting the hydrolysis of tBM blocks with TsOH and their reaction with TMSI, it should be noted that the hydrolysis is reportedly catalytic in nature (7-10), whereas the reaction with TMSI is stoichimetric. Therefore the latter approach may allow one to more easily "dial in" a desired level of methacrylic acid or metal methacrylate. 

However, when (5,5)-3,3 -(2,3-butanediol)-2,2 -bipyridine or (/ )-3,3 -(l, 2-propanediol) -2,2 -bipyridine was used as the ligand [125], copolymers were obtained that had a higher content of isotactic triads. An effective control towards the isospecificity of copolymerisation (<98 % isotacticity in the copolymer) is fulfilled for the copolymerisation of ring-substituted styrene such as p-t-butylstyrene and carbon monoxide with catalysts containing cationic methylpalladium species [117] ... 

Some D/A combinations do not interact strongly enough to bring about thermal copolymerization, but readily yield copolymers under irradiation, for example, p-t-butylstyrene/MAn [23], Some undergo very slow thermal polymerization, while the photopolymerization is much faster, such as St/FN system. Table 2 [37] shows the results of thermal (80 °C) and photocopolymerizations of some monomer pairs. The acceptor strength decreases in the following order ... 

Insertion of carbon monoxide into the methyl-palladium bond of the cationic complex shown in reaction (1), followed by insertion of p-t-butylstyrene has been reported . ... 

Similarly, poly-Cf-methylstyrene is miscible with PMMA, PEMA, PBMA, and PCHMA. Poly-p-methylstyrene, and poly-p-t-butylstyrene show miscibility with polyalkyl(meth)acrylates. However, PS is immiscible with PMMA, PMA, polyethylacrylate (PEA), polybutylacrylate (PBA), or PBMA [Somani and Shaw, 1981],... 

Figure 3.4. Illustration of phase inversion during polymerization (Molau, 1965). Electron micrographs (transmission) of thin sections of a graft copolymer of p-t-butylstyrene with polystyrene (90/10). (a) Polymerized to 5.3 % conversion before the inversion point. The poly(p-t-butylstyrene) phase is white, and the polystyrene phase is black, (b) Polymerized to 7.8% conversion phase inversion is just beginning to occur, (c) The same system polymerized to 13.3% conversion after the phase inversion point.

Other quasiUving polymerizations reported thus far include those of isobutene p-t-butylstyrene indene and styrene The quasiUving polymerization by the technique of slow and continuous addition of monomer is very intriguing. Further studies should be desired, especially in regard to the effects of a very low monomer concentration achieved by this particular technique on the lifetime of the propagating species and on the reversibility of chain transfer reactions. ... 

In addition to a-olefins, p-t-butylstyrene can be used as a comonomer for the isotactic specific copolymerization with carbon monoxide with chiral induction [32]. Whereas bipyridyl as ligand gives a syndiotactic polymer, the Pd-catalyzed polymerization with ligand 11 leads to a polymer with isotacticity of over 98% and high optical activity ([4>]jj -536° (in CH2CI2)) [33, 34]. The BINAPHOS catalyst described above is also effective in this type of copolymerization [25]. 

Styrene (Fisher), p-methylstyrene (Mobil), and t-butylstyrene (DOW) were purified by passing through a column of activated alumina and then carefully degassed to remove all traces of 0. Further purification by vacuum distillation from dibutyl magnesium resulted in anionically pure monomers. 

Catala et al. [143] prepared block copolymers of St with a substituted St,p-ferf-butylstyrene (tBuSt) however, they used the 1-phenylethyl adduct of a slightly different nitroxide, di-ferf-butyl nitroxide, to mediate the polymerization (A-T, Fig. 8) [63,144]. This nitroxide allowed the polymerization to occur under milder conditions than normal for TEMPO-mediated reactions (90 °C vs... 

Storage and loss moduli, G and G" and the dielectric loss, e" of a high-M PI99/PtBS348 miscible blend (Mpi = 9.9 x 10, Mpi g = 3.5 x 10 , w i = 50 wt%) measured at temperatures as indicated. The e" data are multiplied by a factor of 10. (Data taken, with permission, from Watanabe, H., Q. Chen, Y. Kawasaki, Y. Matsumiya, T. Inoue, and O. Urakawa, 2011. Entanglement dynamics in miscible polyisoprene/poly(p-ferf-butylstyrene) blends. Macromolecules 44 1570-1584.)... 

Test of time-temperature superposabillty for the dielectric P data of low-M and middle-M poly-isoprene/poly(p-feri butyl styrene) (PI/PtBS) miscible blends as indicated. In panels (a)-(d), the sample code numbers of the blends denote Kh M of the components. The reference temperature is T, = 90°C for aU blends. The solid curves indicate the e" data of bulk PI corrected for the PI volume fraction in the blends. These curves are shifted along the axis to match their peak frequency with that of the blends. (Etata taken, with permission, from Chen, Q., Y. Matsumiya, Y. Masubuchi, H. Watanabe, and T. Inoue. 2008. Component dynamics in polyisoprene/ poly(4-tert-butylstyrene) miscible blends. MacrvmoJeades 41 8694-8711 Chen, Q., Y. Matsumiya, Y. Masubuchi, H. Watanabe, and T. Inoue. 2011. Dynamics of polyisoprene-poly(p-tert-butylstyrene) diblock copolymer in disordered state. Macnmiolecules 44 1585-1602 Chen, Q., Y. Matsumiya, K. Hiramoto, and H. Watanabe. 2012. Dynamics in miscible blends of polyisoprene and poly(p-terf-butyl styrene) Thermo-rheological behavior of components. Polymer ]. 44102-114.)... 

Chen, Q., Y. Matsumiya, Y. Masubuchi, H. Watanabe, and T. Inoue. 2011. Dynamics of polyisoprene-poly(p-terf-butylstyrene) diblock copolymer in disordered state. Macromolecules 44 1585-1602. 

Watanabe, H., Q. Chen, Y. Kawasaki, Y. Matsumiya, T. Inoue, and O. Urakawa. 2011. Entanglement dynamics in miscible polyisoprene/poly(p-fcrf-butylstyrene) blends. Macromolecules 44 1570-1584. 

We wish to acknowledge Dr. L. J. Fetters for the synthesis of the various t-butylstyrene-styrene block and random polymers done at the University of Akron. D. Griffin and S. Zushma carried out the sulfonation of the polymer precursors and W. Gallagher performed the rheological measurements. The synthesis and rheological characterization of the RAM systems were ably and carefully conducted by J. Wagensommer, E. Habeeb and P. Myer. 

As pointed out in the introduction, unsaturated polyester resins are commonly combined with reactive diluent monomers (Table 12.3). Styrene is most frequently used for this purpose.However, monomers such as methyl methacrylate, diallyl phthalate, " triallyl cyanurate, " vinyl toluene,a -methylstyrene, p-t rt-butylstyrene, and chlorostyrene have also been studied (Table 12.3), showing varying degrees of utility. 

Grafting of substituted styrene monomers such as, a-methylstyrene [139], chlor-methylstyrene [140], i,p-methylstyrene, and p-t rt-butylstyrene prior to sulfonation [119]. However such monomers have poor kinetics and are not easy to graft also, careful optimization of reaction parameters has to be established. 

IRA Irani, C.A. and Cozewith, C., Lower critical solution temperature behavior of ethylene-propylene copolymers in multicomponent solvents, J. Appl. Polym. Sci., 31,1879, 1986. 86KUE Kuecuekyavruz, Z. and Kuecuekyavruz, S., Theta-hehaviour of poly(p-tert-butylstyrene)-b-poly(dimethylsiloxane)-h-poly(p-tert-hutylstyrene), M A rowo/. Chem., 187, 2469, 1986. 86RAE Raetzsch, M.T., Kehlen, H., Browarzik, D., and Schirutschke, M., Cloud-point curve for the system copoly(ethylene-vinyl acetate) + methyl acetate. Measurement and prediction by continuous thermodynamics, J. Macromol. Sci.-Chem. A, 23, 1349, 1986. 

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