Polyurethane—poly interpenetrating polymer networks

Ebdon JR, Hourston DJ, Klein PG (1984) Polyurethane-polysiloxane interpenetrating polymer networks. 1. A polyether urethane-poly(dimethylsiloxane) system. Polymer 25( 11) 1633—1639... 

In this case, an apparent activation energy is determined, and it has higher values than secondary relaxations 100-300 kJ/mol for urethane-soybean oil networks (Cristea et al. 2013), 200-300 kJ/mol for polyurethane-epoxy interpenetrating polymer networks (Cristea et al. 2009), more than 400 kJ/mol for semicrystalline poly(ethylene terephtalate) (Cristea et al. 2010), and more than 600 kJ/mol for polyimides (Cristea et al. 2008, 2011). The glass transition temperature is the most appropriate reference temperature when applying the time-temperature correspondence in a multifrequency experiment. The procedure allows estimation of the viscoelastic behavior of a polymer in time, in certain conditions, and is based on the fact that the viscoelastic properties at a certain tanperature can be shifted along the frequency scale to obtain the variation on an extended time scale (Brostow 2007 Williams et al. 1955). The shift factor is described by the Williams-Landell-Ferry (WLF) equation ... 

VladS, Vlad A, Oprea S (2002) Interpenetrating polymer networks based on polyurethane and polysiloxane. Eur Poly J 38(4) 829—835... 

Xiao H et al. (1990) The synthesis and morphology of semi-interpenetrating polymer networks based on polyurethane-poly(dimethylsiloxane) system. J Poly Sci Part A Poly Chem 28(3) 585-594... 

Dynamic Mechanical Response of In Situ Polyurethane—Poly (methyl methacrylate) Interpenetrating Polymer Networks... 

In our laboratory, much attention has been devoted to the investigation of in situ sequential polyurethane/poly(methyl methacrylate) interpenetrating polymer networks (SEQ PUR/PAc IPNs) (2- ) in which the elastomeric polyurethane network is completely formed in the presence of the methacrylic monomers before the onset of the radical copolymerization which leads to the second network. To each polymerization process corresponds a typical kinetics, which however is not completely independent from each other ( -8). The results obtained with such SEQ IPNs show that the properties do in... 

Fatigue Behavior of Interpenetrating Polymer Networks Based on Polyurethanes and Poly(methyl methacrylate)... 

Although interpenetrating polymer networks (IPNs) are now beginning to be commercially exploited, little is known about many types of engineering behavior, such as fatigue. In this paper, energyabsorbing simultaneous interpenetrating networks (SINs) based on polyether-type polyurethanes (PU) and poly(methyl methacrylate)... 

Nayak, R D.K. Mishra D. Parida K.C. Sahoo M. Nanda S. Lenka P.L. Nayak. Polymers from renewable resources. IX. Interpenetrating polymer networks based on castor oil polyurethane poly(hydroxyethyl methacrylate) Synthesis, chemical, thermal, and mechanical properties. / Appl. Polym. Sci. 1997, 63, 671-679. 

Sreenivasan, K. Synthesis and evaluation of a molecularly imprinted polyurethane-poly (HEMA) semi-interpenetrating polymer networks as membrane. J. Appl. Polym. Sci. 1998, 70, 19-22. 

C. S. Sanmathi, S. Prasannakumar and B. S. Sherigara, Interpenetrating polymer networks based on polyol modified castor oil polyurethane and poly(2-ethoxyethyl methacrylate) Synthesis, chemical, mechanical, thermal properties, and morphology , JAppl Polym Sci, 2004,94,1029-34. 

Electrical properties such as conductivity, resistivity, I (current)-V (voltage) characteristics of vegetable oil-based polyurethane nanocomposites are sometimes influenced by nanocomposite formation with a suitable nanomaterial. BaTiOs superfine fibre-filled castor oil-modified polyure-thane/poly(methyl methacrylate) interpenetrating polymer network nanocomposites exhibit an increase in conductivity between insulator and semiconductor with an increase in nanofibre loading. ... 

A series of castor oil polyurethane/poly(methyl methacrylate) interpenetrating polymer networks (IPNs) and gradient IPNs, cured at room temperature, were prepared by a simultaneous IPN method, and nanocomposites with BaTiOs superfine fibre were reported for the systems. A dose-dependent improvement in thermoelectric and mechanical properties was observed in the nanocomposites compared to the pristine systems. 

S. C. Kim, D. Klempner, K. C. Frisch, and H. L. Frisch, Polyurethane Interpenetrating Polymer Networks II. Density and Glass Transition Behavior of Polyurethane-Poly(methyl methacrylate) and Polyurethane-Polystyrene IPNs, Macromolecules 9(2), 263 (1976). Polyurethane/Polymethacrylate SIN Polystyrene/Polyurethane SIN. Glass transition and density studies. 

M. Matsuo, T. K. Kwei, D. Klempner, and H. L. Frisch, Structure Property Relations in Polyacrylate-Poly(urethane-urea) Interpenetrating Polymer Networks, Polym. Eng. Sci. 10(6), 327 (1970). Polyacrylate/polyurethane urea lENs. Polyurethane/ureapolyacrylate lENs. Morphology via electron microscopy. 

H. Mizumachi and Y. Ogata, One-Step Synthesis of Viscoelastic Properties of Interpenetrating Polymer Networks Comprised of Polyurethane and Poly(methylmethacrylate), Nippon Setchaku Kyokai Shi 12(1) (1976). PU/PMMA SINs. 

Also, isocyanates are used in the formulation of interpenetrating polymer networks (IPNs) (25). A polyester-polsuirethane IPN with a ratio typical for sheet molding compoimd (SMC) is obtained from MDI, poly(caprolactone triol), an im-saturated polyester resin, and styrene monomer (26). IPNs are also reviewed im-der polyurethanes. 

Akay M, Rollins SN. Polyurethane-poly (methyl methacrylate) interpenetrating polymer networks. Polymer 1993 34(9) 1865-73. 

Kelley SS, Ward TC, Glasser WG (1990) Multiphase materials with lignin. Vlll. Interpenetrating polymer networks from polyurethanes and poly(methyl methacrylate). J Appl Polym Sd 41 2813-28... 

Castor oil has found application in the synthesis of interpenetrating polymer networks (IPNs). These materials can be defined as a combination of two polymer networks, at least one of which is synthesized and/or cross-linked in the immediate presence of the other. They are called semi-lPN if just one of the polymers is a network (Athawale et al, 2003). Early reports on castor oil IPNs appeared in 1977 by Yenwo and co-workers. The report discussed the synthesis possibilities via cross-linking of double bonds with sulfur, reaction of hydroxyl groups with diisocyanates, and emulsion polymerizations with saponified ricinoleic acids as emulsifier. Moreover, the IPNs from acrylic polymers, such as polymethyl methacrylate and poly-2-ethoxyethyl methacrylate, and castor oil-based polyurethanes were reported to contribute to the final properties of the material (Cunha et al., 2004 Sanmathi et al, 2004). Incorporation of acrylic moieties into the PU networks increased toughness and thermal properties. In contrast, IPN polyesters derived from castor oil and dibasic acids (e.g. malonic, succinic, glutaric, adipic, suberic, and sebacic acid) were obtained as soft and opaque elastomers (Suthar et al, 2003). 

Athawale VD, Kolekar SL, Rant SS. 2003. Recent Developments in Polyurethanes and Poly(acrylates) Interpenetrating Polymer Networks. J Macromol Sci Part C-Polym Rev 43(l) l-26. 

Cunha FOV, Melo DHR, Veronese VB, Forte MMC. 2004. Study of castor oil polyurethane-poly (methyl methacrylate) semi-interpenetrating polymer network (SIPN) reaction parameters using a 23 factorial experimental design. Mater Res 7 539-543. 

Klein PG, Ebdon JR, Hourston DJ (1988) Polyurethane-polysiloxane interpenetrating networks 3. Polyetherurethane-poly(phenylmethylsiloxane) systems. Polymer 29(6) 1079—1085... 

Yu. S. Lipatov, L. V. Karabanova, T. S. Khramova, and L. M. Sergeeva, Study of Physicochemical Properties of Interpenetrating Polyurethane and Poly(urethane acrylate) Polymer Networks, Vysokomol. Soedin. Ser. A 20(1), 46 (1978). Thermodynamics and Swelling of IPNs and PU-based IPNs. 

Siloxane containing interpenetrating networks (IPN) have also been synthesized and some properties were reported 59,354 356>. However, they have not received much attention. Preparation and characterization of IPNs based on PDMS-polystyrene 354), PDMS-poly(methyl methacrylate) 354), polysiloxane-epoxy systems 355) and PDMS-polyurethane 356) were described. These materials all displayed two-phase morphologies, but only minor improvements were obtained over the physical and mechanical properties of the parent materials. This may be due to the difficulties encountered in controlling the structure and morphology of these IPN systems. Siloxane modified polyamide, polyester, polyolefin and various polyurethane based IPN materials are commercially available 59). Incorporation of siloxanes into these systems was reported to increase the hydrolytic stability, surface release, electrical properties of the base polymers and also to reduce the surface wear and friction due to the lubricating action of PDMS chains 59). 

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