Siloxanes block copolymers, properties

L.M. Robeson, A. Noshay, M. Matzner and C.N. Merian, Physical Property Characteristics of Polysulfone/poly(dimethyl siloxane) Block Copolymers, Angew. Makro-mol. Chem. 29, 47 (1973). 

US 5,028,681 (American) 1991 Novel poly(imide siloxane) block copolymers and process for their preparation General Electric EN Peters Injection moldable block copolymers with high IV and excellent chemical/physical properties. Blends useful for impact modification Novel siloxane-imide block copolymers and a process for their preparation are covered. The method involves reacting a hydroxy-terminated polyimide oligomer with a siloxane oligomer with dimethylamino, acetyl or chlorine end-groups... 

Pei X, Chen G, Fang X. Synthesis and properties of poly(imide siloxane) block copolymers with different block lengths. J Appl Polym Sci 2013 129(6) 3718-27. 

Novak, I. Sysel, P. Zemek, J. Spirkova, M. Velic, D. Aranyosiova, M. Flo-rian, S. Poliak, V. Kleinova, A. Lednicky, F. Janigova, I., Synthesis and Adhesion Properties of (Polyimide-Siloxane) Block Copolymers. Eur. Polym. J. 2009, 45, 57-69. 

Park HB, Kim JK, Nam SY, Lee YM (2003) Imide-siloxane block copolymer/silica hybrid membranes preparation, characterization and gas separation properties. J Membr... 

Silphenylene-Siloxane Copolymers.—The thermal properties vctsus structure for poly(tetramethyl-p-silphenylensesiloxane) and (tetramethyl-p-silphenylene/di-methylsiloxane) block copolymers have been compared. The homopolymer has a m.p. of 160°C, heat of fusion of 54.4 J/g and Tg of —20°C. The Tg of the copolymer varies monotonically with inojeased dimethylsiloxane content, from — 20 to —123 °C. Data have been reported on the crystallization kinetics and morphology of blends of fractionated poly(tetramethyl-p-silphenylenesiloxanes). The chemical degradation of poly(tetramethyl-/ -silphenylenesiloxane/dimethyl-siloxane) block copolymers by HF has been reported. In 48% HF at 30 °C, preferential attack occurs at the Si—O bond, particularly those of the MejSi—O non-crystalline components, in copolymers containing 15, 35, and 52% poly-dimethylsiloxane. - Further data have been reported on the crystal structure and fold conformation of poly(tetramethyl-/>-silphenylenesiloxane)s, obtained from X-ray diffraction studies. ... 

The synthesis and characterization of poly(hexamethylene sebacate-tiimethyl-siloxane) block copolymers, prepared by coupling Cl- or McjNH-terminated dimethylsiloxanes with OH-terminated poly(hexamethylene sebacate), have been studied. The copolymers containing 19—90% siloxane were characterized by n.m.r., viscosity, DSC and CPC. All the polymers were found to be crystalline. The copolymers containing <69% siloxane, when cast from solution or melts, indicated a reduction in spherulite size as the siloxane concentration increased, although only a small m.pt. depression was observed. All the copolymers have critical surface tensions similar to dimethylsiloxane homopolymers. Polycarbonate-Siloxane Copolymers.—A model has been proposed to predict the micromorphology and mechanical properties of block copolymers of bisphenol-A polycarbonate and poly(dimethylsiloxane). N.m.r. data upon 65 35 (wt%) copolymer of poly(dimethylsiloxane) and bisphenol-A polycarbonate, with block lengths of 20—100 monomer units, were found to be in agreement with the predictions of a spin-diffusion model. ... 

Nanotechnology and molecular electronics are progressing rapidly. As semiconductor devices approach their physical limits, researchers are trying to find ways to decrease the size of microelectronic circuits. Thus, cylindrical micelles composed of a ferrocenylsilane-siloxane block copolymer assemble on a silicon surface to form linear features. The micelle lines can then be transformed into a pattern of ceramic nanolines and create conjugated polymer nanowires by controlled chain polymerization. The micelle nanostructures can be converted into magnetic ceramic nanopatterns. It is possible that these lines will display magnetic, conductive and semiconductive properties. 

See also PBT degradation structure and properties of, 44-46 synthesis of, 106, 191 Polycaprolactam (PCA), 530, 541 Poly(e-caprolactone) (CAPA, PCL), 28, 42, 86. See also PCL degradation OH-terminated, 98-99 Polycaprolactones, 213 Poly(carbo[dimethyl]silane)s, 450, 451 Polycarbonate glycols, 207 Polycarbonate-polysulfone block copolymer, 360 Polycarbonates, 213 chemical structure of, 5 Polycarbosilanes, 450-456 Poly(chlorocarbosilanes), 454 Polycondensations, 57, 100 Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT), 25 Polydimethyl siloxanes, 4 Poly(dioxanone) (PDO), 27 Poly (4,4 -dipheny lpheny lpho sphine oxide) (PAPO), 347 Polydispersity, 57 Polydispersity index, 444 Poly(D-lactic acid) (PDLA), 41 Poly(DL-lactic acid) (PDLLA), 42 Polyester amides, 18 Polyester-based networks, 58-60 Polyester carbonates, 18 Polyester-ether block copolymers, 20 Polyester-ethers, 26... 

Polysiloxane based block copolymers have also been examined with respect to their transport properties, because these copolymers are of special interest as membranes in various biomedical applications 376). The combination of good mechanical, dielectric, permeation and film formation properties of siloxane-carbonate segmented copolymers have led to their use as blood oxygenation, dialysis and microelectrode membranes 392 394. ... 

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