Poly methacrylate block copolymers

Breiner T, Kreger K, Hagen R, Hackel M, Kador L, Muller AHE, Kramer EJ, Schmidt H W. 2007. Blend of poly(methacrylate) block copolymers with photo addressable segments. Macromolecules 40 2100 2108. 

Blends of poly(methacrylate) Block Copolymers with Photoaddressable Segments. Macromolecules, 2007,40, 2100-2108. 

Breiner, T., Kreger, K., Hagen, R., Hackel, M., Kador, L., Muller, A. H. E., Kramer, E. J. and Schmidt, H.-W. (2007) Blends of poly(methacrylate) block copolymers with photoaddressable polymers . Macromolecules, 40,2100-2108. 

Gong, Y., Huang, H., Hu, Z., Chen, Y, Chen, D Wang, Z. and He, X. (2006) Inverted to normal phase transition in solution-cast polystyrene-poly(methyl methacrylate) block copolymer thin films. Macromolecules, 39, 3369-3376. 

Various substituted styrene-alkyl methacrylate block copolymers and all-acrylic block copolymers have been synthesized in a controlled fashion demonstrating predictable molecular weight and narrow molecular weight distributions. Table I depicts various poly (t-butylstyrene)-b-poly(t-butyl methacrylate) (PTBS-PTBMA) and poly(methyl methacrylate)-b-poly(t-butyl methacrylate) (PMMA-PTBMA) samples. In addition, all-acrylic block copolymers based on poly(2-ethylhexyl methacrylate)-b-poly(t-butyl methacrylate) have been recently synthesized and offer many unique possibilities due to the low glass transition temperature of PEHMA. In most cases, a range of 5-25 wt.% of alkyl methacrylate was incorporated into the block copolymer. This composition not only facilitated solubility during subsequent hydrolysis but also limited the maximum level of derived ionic functionality. 

Narrow molecular weight distribution PMMA-fc-poly(2-perfluorooclyle-thyl methacrylate) block copolymers (Scheme 2) were synthesized in THF at... 

Non-ionic polymers have also been blended with ionic block copolymers. Poly(vinyl phosphanate)-l7-polystyrene and PS-l -SPS have been blended with PPO. In both cases, improvements were seen in MeOH permeability over that of fhe unmodified block copolymers and conductivity values dropped as a function of increasing PPO confenf. PVDF has been blended wifh SEES in order fo improve its mechanical and chemical stability, but aggregation was found fo be a problem due fo incompafibility between components. However, it was found that a small amount (2 wt%) of a methyl methacrylate-butyl acrylate-methyl methacrylate block copolymer as com-patibilizer not only led to greater homogeneity but also improved mechanical resistance, water management, and conductivity. ... 

N. Martinez-Castro, M.G. Lanzendorfer, A.H.E. Muller, J.C. Cho, M.H. Acar, and R. Faust, Polyisobutylene stars and polyisobutylene-block-poly(tert-butyl methacrylate) block copolymers by site transformation of thiophene end-capped polyisobutylene chain ends, Macromolecules, 36(19) 6985-6994, September 2003. 

Krappe U, Stadler R et al (1995) Chiral assembly in amorphous ABC triblock copolymers. Formation of a helical morphology in polystyrene-block-polybutadiene-block-poly(methyl methacrylate) block copolymers. Macromolecules 28 4558 1561... 

Tphe surface activity of block copolymers containing dimethylsiloxane units as one component has received considerable attention. Silicone-poly ether block copolymers (1,2,3) have found commercial application, especially as surfactants in polyurethane foam manufacture. Silicone-polycarbonate (4, 5), -polystyrene (6, 7), -polyamide (8), -polymethyl methacrylate (9), and -polyphenylene ether (10) block copolymers all have surface-modifying effects, especially as additives in other polymeric systems. The behavior of several dimethylsiloxane-bisphenol A carbonate block copolymers spread at the air—water interface was described in a previous report from this laboratory (11). Noll et al. (12) have described the characteristics of spread films of some polyether—siloxane block co-... 

Kim HC, Nam KH, Jo WH. The effect of a styrene-methyl methacrylate block copolymer on the morphological, rheological and mechanical properties of poly(2-6-dimethyl-l,4-phenylene ether) (PPE) and poly(hydroxyether of bis-phenol A) (phenoxy) blends. Polymer 1993 34 4043-4051. 

Microreactors have also been used for ionic polymerization or polycondensation processes. Nagaki et al. [136] have synthesized polystyrene-poly(alkyl methacrylate) block copolymers by butyllithium initiated anionic polymerization in an integrated flow microreactor system. A high level of control of molecular weight was achieved at temperatures between -28 and +24 °C due to fast mixing, fast heat transfer, and residence time control. Santos and Metzger... 

Acetal-PEG-Poly(2-yy,N-dimethylaminoethyl Methacrylate) Block Copolymer (46)... 

Long, T.E., Broske, A.D., Bradley, D.J., et al., 1989. Synthesis and characterization of poly(tert-butyl methacrylate-b-isoprene-b-tert-butyl methacrylate) block copolymers by anionic techniques. J. Polym. Sci. Part A Polym. Chem. 27 (12), 4001 012. 

Figure 9-19. A universal gel-permeation chromatography calibration curve obtained from measurements on linear poly(styrene) (O), comb-branched poly(styrene) (O ), star-branched poly(styrene) ( ), poly(methyl methacrylate) ( ), poly(vinyl chloride) (a) c -l,4-poly-(butadiene) (A), poly(styrene)-poly(methyl methacrylate) block copolymer (Qj ), random copolymer from styrene and methyl methacrylate O), and ladder polymers of poly(phenyl siloxanes) ( ) (according to Z. Grubisic, P. Rempp, and H. Benoit).

Micellization of poly(isobutylene)-( tocfc-poly(methacrylic acid) copolymers with short hydrophobic and long PE blocks has been studied [124-127] by DLS, SLS, SANS, and pyrene titration experiments supported by cryo-TEM imaging. It was unambiguously demonstrated that at high pH, when the poly(methacrylic acid) blocks are fully ionized, the aggregation number increases whereas the hydrodynamic radius decreases as a function of salt concentration. Both dependencies can be approximated by power laws with exponents close to those predicted by theory (87), (89), which again points to the dynamic nature of these micelles. 

Nagaki A, Miyazaki A, Yoshida J (2010) Synthesis of polystyrenes-poly(alkyl methacrylates) block copolymers via anionic polymerization using an integrated flow microieactor system. Macromolecules 43 8424—8429... 

In addition to the microphase separation phenomenon, in the presence of an interface, the affinity of one of the blocks by the interface influences the flnal rearrangement of the block copolymer at the outmost surface as has been already reported, for instance by Coulon et al. [96] for the case of polystyrene-6-poly (methyl methacrylate) block copolymers (Fig. 5.12). Initially, upon spin coating the block copolymers are rather disordered due to the fast evaporation process. However, upon annealing reorganization occurs and nanometer scale phases rich in each of the components are observed. Finally, the difference in the surface energies of the components forces the orientation of these domains parallel to the surface, with the lower-surface-energy block located at the surface [96-98]. 

The one-pot synthesis of poly(cyclooctadiene)-h-poly(methyl methacrylate) block copolymers via the combination of ROMP and ATRP mechanism was reported by Bielawski et al. (Scheme 11.47) [209]. The single rutheniumaUcylidene complex successfully catalyzed two mechanistically distinct polymerizations, simultaneously. The obtained block copolymer showed rather moderate polydispersities, however, at about 1.6. 

Da (PDI = 1.21). The reaction temperatiire was not clearly defined, however. Subsequently, the same group reported details of the successful formation of a poly(ethylene oxide) (PEO)-poly(hydroxypropyl methacrylate) block copolymer using a pre-modified macro initiator [20]. 

The preparation of poly(IB-h-methyl methacrylate or hydroxyethyl methacrylate) block copolymers has also been accomplished by the combination of hving cationic and anionic polymerization. First DPE end-functionahzed PIB (PIB-DPE) was prepared from the reaction of living PIB and l,4-bis(l-phenylethenyl)benzene (PDDPE), followed by the methylation of the resulting diphenyl carbenium ion with dimethylzinc. PIB-DPE was quantitatively metalated with u-butyhithium in THF at room temperature and the resulting macroinitiator could efficiently initiate the living polymerization of methacrylate monomers at —78°C yielding block copolymers with high block efficiency [236]. 

For example, methyl methacrylate block copolymers are much less studied than those of styrene. Anion chain transfer occurs at the pendent ester group, drastically reducing the yield of block copolymers. Poly(methyl methacrylate-b-isoprene) has been prepared, however, by using an ingenious chain cap of l,l -diphenylethyl-ene(27,28). i l diphenylethylene will not anionically homopolymerize, therefore it adds only one mer to the macroanion. This anion is more stable in the presence of methyl methacrylate, but will initiate further polymerization. Other workers have reported the preparation of isoprene-methyl methacrylate block copolymers by sequential addition to "living" polyisoprene anions(29,30),... 

Many combinations of various acrylate and methacrylate block copolymers were obtained by ATRP and the knowledge gathered by these approaches has led to the synthesis of even more complex AB copolymers consisting of PMMA and poly (vinylacetylene), or PEO and poly(acrylonitrile) by incorporating various types of halide-based reagents leading to well-defined block copolymers. The synthetic route of the latter combination is given in Scheme 17. 

Figure 6.20. Segment distributions of a styrene-(methyl methacrylate) block copolymer (relative molecular masses of each block were in the range 48 000-65 000) at an interface between polystyrene (relative molecular mass in the range 110000-127 000) and poly(methyl methacrylate) (relative molecular mass in the range 107000-146 000), revealed by a series of neutron reflection experiments in which various parts of the copolymer and/or one of the homopolymers was labelled with deuterium. The bold lines are the segment density profiles for all styrene and methyl methacrylate segments, summed over both the homopolymer and the copolymer the solid lines are the homopolymers, and the dotted lines are the styrene and methyl methacrylate blocks of the copolymer. After Russell et al. (1991).

Figure 7.4. Fracture energies of interfaces reinforced by block copolymers as a function of the effective areal density of chains crossing the interface. Triangles and squares are for polystyrene/poly(2-vinyl pyridine) interfaces reinforced with styrene-2-vinyl pyridine block copolymers (Creton et al. 1992) circles are for poly(xylenyl etherypoly(methyl methacrylate) interfaces reinforced with styrene-methyl methacrylate block copolymers (Brown 1991a, b). After Creton et al. (1992).

Figure 5.14 Three-dimensional presentation of molecular mass distribution and chemical composition distribution for a poly(styrene-methyl methacrylate) block copolymer [72].

Figure 5.22 50 MHz CP/MAS CNMR spectra of (a) polystyrene/poly(methyl methacrylate) block copolymer (PS/PMMA) and (b) perdeuteropolystyrene/poly(methyl methacrylate) block copolymer (PSD/PMMA) [48]. m, PMMA s, PS and +, spinning sideband.

Reprinted from J. Pinto, et al.. Temperature influence and CO2 transport in foaming processes of poly(methyl methacrylate)-block copolymer nanocellular and microcellular foams. Journal of Supercritical Fluids, 94 (2014) 198-205 with permission from Elsevier. 

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