Styrene, graft copolymers with

We have studied the dispersibility of several pure PVAc-styrene graft copolymers with one PS branch in various selective solvents mainly at room temperature5. The experiment was done with two kinds of dried samples one was recovered from a tetrahydrofuran solution by pouring it into water and the other from a benzene solution which was poured into n-hexane. Let us refer to the former sample as A and the latter sample as B. Due to the difference in solubility of each polymer sequence in those solvents, sample A is supposed to have approximately such a microstructure that PVAc chains are extended and PS chains collapsed, while sample B has the inverse structure. A similar tendency was also pointed out by Merrett12. The results are summarized in Table 2. 

In addition to providing fully alkyl/aryl-substituted polyphosphasenes, the versatility of the process in Figure 2 has allowed the preparation of various functionalized polymers and copolymers. Thus the monomer (10) can be derivatized via deprotonation—substitution, when a P-methyl (or P—CH2—) group is present, to provide new phosphoranimines some of which, in turn, serve as precursors to new polymers (64). In the same vein, polymers containing a P—CH group, for example, poly(methylphenylphosphazene), can also be derivatized by deprotonation—substitution reactions without chain scission. This has produced a number of functionalized polymers (64,71—73), including water-soluble carboxylate salts (11), as well as graft copolymers with styrene (74) and with dimethylsiloxane (12) (75). 

By maintaining the first-stage reactor just beyond the phase inversion point, the dispersed rubber phase is relatively rich in dissolved styrene. As polymerization subsequently proceeds in the LFR s, the dissolved styrene will react to form either a graft copolymer with the rubber or a homopolymer. The latter will remain within the rubber droplet as a separate occluded phase. Achieving the first-stage reactor conversion and temperature by recycling a portion of the hot second reactor effluent may permit simplification of the first reactor temperature control system. 

II. B polyethylene glycol, ethylene oxide, polystyrene, diisocyanates (urethanes), polyvinylchloride, chloroprene, THF, diglycolide, dilac-tide, <5-valerolactone, substituted e-caprolactones, 4-vinyl anisole, styrene, methyl methacrylate, and vinyl acetate. In addition to these species, many copolymers have been prepared from oligomers of PCL. In particular, a variety of polyester-urethanes have been synthesized from hydroxy-terminated PCL, some of which have achieved commercial status (9). Graft copolymers with acrylic acid, acrylonitrile, and styrene have been prepared using PCL as the backbone polymer (60). 

Fawcett, A. H. Foster, A. B. Hania, M. Hohn, M. Mazebedi, J. L. McGaffery, G. O. Mullen, E. Toner, D. Silicone Graft Copolymers with Acrylonitrile, Ghloroprene, Styrene, Methylmethacrylate, and an Olefin. In Synthesis and Properties of Silicones and Silicone-Modified Materials-, Clarson, S. J., Fitzgerald, J. J., Owen, M. J., Smith, S. D., Van Dyke, M. E., Eds. ACS Symposium Series 838 American Chemical Society Washington, DC, 2003 pp 318-328. 

In Table III the specific conductance and electro-osmotic coefficient (3) for the SPS membrane are shown together with the data for a conventional ion-exchange membrane, AMF C103 (16,17) (polyethylene-styrene graft copolymer containing sulphonic acid groups). It appears that there is a close similarity in properties of both membranes. ... 

We found also that the amino-content of the polyamine-styrene graft copolymer, SAX (x is the polyamine content in wt.%) correlates closely with the adsorption behavior of FN or VN as it also does with the adhesivity of bovine aortic endo-thelial cells to the SA copolymer surface, as will be discussed in Sect. 4.4. 

M.K. Laughner, Molding compositions with methyl (meth)acrylate-butadiene-styrene graft copolymers, US Patent 5 087 663, assigned to The Dow Chemical Company (Midland, MI), February 11,1992. 

High impact strength thermoplastic resins can be prepared by mixing a styrene/acrylonitrile copolymer with rubber particles. In general, the styrene/acrylonitrile copolymer is prepared by the graft copolymerization of styrene and acrylonitrile in the presence of rubber itself (17). 

The ozonization method has been extended to the most varied polymer/monomer systems, such as polybutadiene-03 with acrylamide, methyl methacrylate or styrene, cellulose-03 with styrene or acrylonitrile (127), starch-03 with styrene (126). In this last case the formation of some homopolystyrene as side-product has been mentionned by the authors. The starch-styrene graft copolymers are claimed to be good emulsifiers for water-oil suspensions. 

Comparison of Methyl Methacrylate-Butadiene-Styrene with Acrylonitrile-Butadiene—Styrene Graft Copolymers... 

Such hydrophilic macromonomers (DPn=7-9) were radically homopolymer-ized and copolymerized with styrene [78] using AIBN as an initiator at 60 °C in deuterated DMSO in order to follow the kinetics directly by NMR analysis. The macromonomer was found to be less reactive than styrene (rM=0.9 for the macromonomer and rs=1.3 for styrene). Polymerization led to amphiphilic graft copolymers with a polystyrene backbone and poly(vinyl alcohol) branches. The hydrophilic macromonomer was also used in emulsion polymerization and copolymerized onto seed polystyrene particles in order to incorporate it at the interface. 

Fig. 12. Thin-layer chromatograms of the PS homopolymer, the PVAc homopolymer, the isolated PVAc-styrene graft copolymer (PVAc-g-PS) and mixtures of PS and PVAc-g-PS with different mixing ratios. Developer chloroform...

Figure 17 shows the chromatogram where the polymer concentration c is plotted against the elution volume. The sample used is a mixture of PVAc-styrene graft copolymer, PVAc and PS. Silica gel is charged with benzene to a column... 

It is well known that primary amines are efficient initiators for the polymerization of Leuch s anhydrides (oxazolidinediones) and that initiation proceeds by the addition of the amine to the monomer. This pathway has been utilized recently to synthesize polypeptide macromonomers bearing a terminal p-vinylbenzyl group 88). Copolymerization of these macromonomers with a vinylic or acrylic comonomer yields graft copolymers with polypeptide grafts. Alternately, the monomer adduct (IV) was copolymerized with styrene, and the primary amine functions of this polymer were used to initiate the polymerization of an oxazolidinedione whereby polypeptide grafts are formed 89). Such graft copolymers may be of interest for biomedical applications. 

The macromonomers thus obtained exhibit molecular weights as low as 1000. They were copolymerized with monomers such as styrene and butyl acrylate whereby graft copolymers with poly(vinyl chloride) grafts were obtained. 

The same type of graft copolymers with a polystyrene backbone and polypeptide grafts has been synthesized by a different route 89) The monoadduct of DVB and N-ethylethylenediamine was copolymerized with styrene, yielding a random copolymer with pendent primary amine functions. The latter were used as initiators for the subsequent polymerization of the NCA derived from benzyl L-glutamate. 

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