Functionalization of polystyrene

Cross-linked polystyrene can be acylated with aliphatic and aromatic acyl halides in the presence of A1C13 (Friedel-Crafts acylation, Table 12.1). This reaction has mainly been used for the functionalization of polystyrene-based supports, and only rarely for the modification of support-bound substrates. Electron-rich arenes (Entry 3, Table 12.1) or heteroarenes, such as indoles (Entry 5, Table 15.7), undergo smooth Friedel-Crafts acylation without severe deterioration of the support. Suitable solvents for Friedel-Crafts acylations of cross-linked polystyrene are tetrachloroethene [1], DCE [2], CS2 [3,4], nitrobenzene [5,6], and CC14 [7]. As in the bromination of polystyrene, Friedel-Crafts acylations at high temperatures (e.g. DCE, 83 °C, 15 min [2]) can lead to partial dealkylation of phenyl groups and yield a soluble polymer. 

Figu re 10.7. Polystyrene/ HDPE composite tensile strength as a function of polystyrene content. 

As an undergraduate, Jonathan Behrendt studied for a B.Sc. in Chemistry and Law from the University of Exeter, where he was awarded a 2.1 hons. degree in 2001. He went on to study for a Ph.D. in chemistry at University College London, with Dr. Helen Hailes. His Ph.D. research project focused on the use of polymeric supports for the synthesis of structurally defined oligomers and cyclic ethers. Having been awarded his Ph.D. in 2005, he is currently working on the synthesis and functionalization of polystyrene microspheres as cellular delivery vectors, in the research group of Dr. Andy Sutherland at Aston University. 

Luis, S. V., Burguete, M. I. and Altava, B. A novel method for the functionalization of polystyrene resins through long aliphatic spacers, React. Fund. Polym., 1995,26,75-83. 

This can be clearly seen in the comparison of viscosity functions of polystyrene 1 and polystyrene 2. If we add a very high-molecular weight component to polystyrene 2, we obtain polystyrene 3. It is therefore evident that the bimodal molar mass distribution causes the shear thinning to increase further, although not as far as the polydispersity change of the molar mass distribution between polystyrene 1 and polystyrene 2. In the case of higher shear rates, all flow curves proceed to similar viscosity functions. 

Farall MJ, Frechet JMJ, Bromination and lithiation two important steps in the functionalization of polystyrene resins, J. Org. Chem., 41 3877-3882, 1976. 

Marti E, Kaiserberg E, Moukhina E (2006) Heat capacity functions of polystyrene in glassy and in liquid amorphous state and glass transition DSC and TMDSC study. J Therm Anal Cal 85 505-525... 

FUNCTIONALIZATION OF POLYSTYRENE. II SYNTHESIS OF CHELATING POLYMERS BY ALKYLATION OF 4-AMINOMETHYLPOLYSTYRENE... 

A. Warshawsky, R. Kalir and A. Paichornik, Functionalization of polystyrene. I. Alkylation with substituted benzyl halide and benzyl alcohol ci>m-pounds, J. Org. (. hem.. 4. (197K) 3151. 

M. Stern. M. Fridkin and A. Warshawsky. Functionalization of polystyrene. HI. Synthesi.s of polymeric thiol reagents. J. Polym. Sci.. Polym. Chem. Fd.. 20 (19X2) 1469. 

Fig. 15.5. Form functions of polystyrene in the melt experimental result obtained by neutron scattering. (From Rawiso and Picot.11)...

Figure 9. Integral distribution functions of polystyrenes synthesized under Poisson conditions in two solvents (10)...

Notation. Throughout this chapter the degree of functionalization of polystyrene is reported as DF, the fraction of rings substituted. The % yield of a transformation on a polymer is 1(X) x DF(product)/DF(reactant). The % cross-linking of a polystyrene is reported as wt % divinylbenzene (DVB) in the monom mix at the start of copolymerization. Technical DVB typically contains 55% active DVB meta and para) and 45% ethylvinylbenzenes. Thus a 2% cross-linked polystyrene also contains 1.6% ethylvinylbenzene. Circled P is used for polystyrene, either all para or mixed meta and para isomers. 

A method for terminal functionalization of polystyrene chains relying on platinum-catalyzed hydrosilylation of w-silyl hydride... 

Polymers with stable backbones such as polystyrene, polyethylene, and polypropylene can be functionalized. Functionalization of polystyrene has received considerable attention, because it is a unique polymer with aromatic rings capable of undergoing many nucleophilic as well as electrophilic reactions. A resin recently introduced on the market is based on sulfonated polystyrene. Applications for this resin include ion-exchange material and catalyst binding materials. 

TOF-SIMS ion yields for polystyrene deposited on a silver substrate. A. Secondary-ion yield as a function of polystyrene concentration. B. Secondary-ion yield as a function of surface coverage. (Reprinted with permission from Ref. 12, Copyright 1994 American Chemical Society)... 

Kent, et al. [107] report Rg and Dp of 233 and 930 kDa polystyrenes in 7, 66, 70, 840, and 1300 kDa polymethylmethacrylates in ethyl benzoate (for static light scattering) cind toluene (for QELSS). Except for the 66 kDa PMMA, M /Mp <1.10. D of the polystyrene was mecisured cis a function of polystyrene concentration, thereby obtaining both Dp and the initial linear slope of D against polystyrene concentration. Figure 24d shows Rg of the 930 kDa pol5rstyrene as a function of PMMA concentration. Rg follows... 

Weibel, D.E., Kessler, F., and da Silva Mota, G.V, (2010) Selective surface functionalization of polystyrene by inner-shell monochromatic irradiation and oxygen exposure. Polym. Chem., 1, 645-649. 

Table 4. The influence of chloromethylation procedures and of the degree of cross-linkage on the functionalization of polystyrenes, according to Frank and Hagenmaier [701...

Tongta, A. Liapis, A.I., and Hagen, S., Synthesis of anion exchange adsorbent particles by surface functionalization of polystyrene-divinylbenzene based spherical porous matrices, Sep. Technol., 6(1), 77-90 (1996). 

Scheme 2. Functionalization of polystyrene and subsequent enzyme attachment...

Fig. 8. Tensile strength as a function of polystyrene molecular weight for graft copolymers with NR and Cariflex IR 305.

A method for terminal functionalization of polystyrene chains relying on platinum-catalyzed hydrosilylation of cu-silyl hydride functionalized polymers with bis(trimethylsilyl)allylamine was developed. KHMDS has been treated with allyl bromide in HMDS (0 °C, 1 h) to provide the requisite TMS-protected allylamine. ... 

Hashimoto T, Iguchi N, Oyamada J, Kitamura T. Direct functionalization of polystyrenes by platinum(II)-catalyzed hydroarylation. A new methodology for utilization of... 

Scbeme 5. Functionalization of polystyrene by polymer-analogous introduction of the monometh-oxytrityl chloride group... 

Epoxy functionalization of polystyrene via the above mechanism was evidenced by H-NMR and C-NMR analysis of the resulting polymer. 

Aside from encapsulation of proteins, much work has been done on the surface functionalization of microparticles for cellular interaction and proliferative effects. Surface modification of PLGA micro-spheres with an amine-terminated dendrimer improved long-term proliferation of chondrocytes without observed changes in the cell phenotype, as compared to monolayer culture systems (Thissen et al. 2006). Additionally, surface functionalization of polystyrene magnetic microbeads with the DLL4 notch ligand used in coculture has been shown to efficiently generate T cells from mouse bone marrow hematopoietic stem cells (Taqvi et al. 2006). 

Figure 1.13 Stability ratio (a) and electrophoretic mobility (b) of precipitated calcium carbonate (PCC) as a function of polystyrene latex addition, in distilled water (DW) and in tap water (TW).

Figure 6. Plot of Raman intensity of polystyrene films on silver islands on glass substrates as a function of polystyrene film thickness. The silver island film has an average (mass) thickness of lOOA.

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