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Urethane-modified methacrylates

Polyurethane-acrylic coatings with interpenetrating polymer networks (IPNs) were synthesized from a two-component polyurethane (PU) and an unsaturated urethane-modified acrylic copolymer. The two-component PU was prepared from hydroxyethylacrylate-butylmethacrylate copolymer with or without reacting with c-caprolactonc and cured with an aliphatic polyisocyanate. The unsaturated acrylic copolymer was made from the same hydroxy-functional acrylic copolymer modified with isocyanatoethyl methacrylate. IPNs were prepared simultaneously from the two-polymer systems at various ratios. The IPNs were characterized by their mechanical properties and glass transition temperatures. [Pg.297]

Photopolymerization of Urethane-Modified Methacrylates for Insulating Magnet Wire... [Pg.280]

Urethane-modified acrylates and methacrylates are known from the literature (I, 2). These monomers are high boiling and viscous enough to be suitable for solventless applications. Two interesting monomers of this type have been prepared from readily available commercial materials. Compound I is a monourethane monomethacrylate it is a liquid with a viscosity of 40 cps at 28°C. Compound II is a diurethane dimethacrylate it is a white, waxy solid that melts around 65°C. Several other monomers of this type have been examined, but these two form the basis of this work. [Pg.281]

Other coating systems contain cationically modified copolymers obtained by polymerization of acrylic monomers in presence of unsaturated polyurethane macromonomer [22], and water-dilutable dispersions of cationically modified and urethane modified methacrylic copolymers obtained by solution polymerization [23]. [Pg.171]

The majority of resins are composed of two dimethacrylate monomers, 2,2 -bis [4(2-hydroxy-3-methacryloyloxypropyloxy)phenyl] propane (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) [22-28]. Typically, TEGDMA or other methacrylate monomers are added as viscosity modifiers to Bis-GMA to make the solution less viscous and more appropriate for clinical use. These diluents also allow for better distribution of the components during manufacture of these composite systems. Another common monomer used to make dental composites, especially those manufactured in Europe, is urethane dimethacrylate [24,29, 30], Ethoxy bisphenol A dimethacrylate is another modification of the Bis-GMA monomer that can be used to make a more hydrophobic polymer that would better withstand the wet oral environment. Other diluents include low viscosity diacrylates and dimethacrylates. Table 1 lists some of these monomers [31-37]. [Pg.181]

Polyurethane hydrogels derived from UV curable urethane prepolymer and hydrophilic monomers were prepared and their properties were evaluated. The urethane prepolymer used in this study contained well-defined hard segments centered with a polyether-based soft segment and end-capped with methacrylate groups. The hydrophilic monomers studied were 2-hydroxyethyl methacrylate (HEMA), N-vinyl pyrrolidone, and glycerol methacrylate. Methacryloxypropyl tris(trimethysiloxy) silane (TRIS) was also used in some cases to modify properties. All compositions were UV... [Pg.175]

When the process involves two competitive reactions, some people prrfer to call those modified polymers interpenetrated polymer networks (IPNs) [5]. The formation of a polyether-urethane network in a loosely crosslinked poly(methyl methacrylate) matrix to increase its toughness can serve as one of the examples. From a general point of view, the analysis of the reaction-induced phase separation is the same (perhaps more complex) for IPNs than for rubber-modified epoxies or for high-impact polystyrene. [Pg.101]

CAS 868-77-9 EINECS/ELINCS 212-782-2 Uses Crosslinkable paint resin binder for textiles/paper adhesives urethane methacrylates reactive thinners grafting of textile fibers scale inhibitors adhesion promoter for polymers hydrophilic polymers lt.-cuting polymer systems rubber modifiers contact lenses photopolymer plates photoresists... [Pg.523]

Radiation curable adhesives can be based on raw materials that are not greatly different from those used in acrylic adhesives (first, second, and third generations), epoxy adhesives, urethane adhesives, and anaerobic adhesives. The formulation approach, however, is somewhat different. Very important is that no solvents are used to thin the resins a monomer reactive diluent is used instead. The monomer must be matched with the resin to give the desired set of properties with respect to adhesion, substrate, flexibility or stiffness, cure behavior, and durability of the cured product. Most of the radiation curable adhesives have an acrylate (or methacrylate) basis many of the acrylics are modified. [Pg.759]

Vinyl esters are thermosetting resins that consist of a polymer backbone with an acrylate or methacrylate termination. The backbone component of vinyl ester resins can be derived from epoxide, polyester or urethane but those based on epoxide resins have most commercial significance. Bisphenol A epoxy formed vinyl esters were designed for chemical resistance and commonly formulated for viscosity for use in filament winding of chemical containers. Typically styrene is used as a reactive dilutent to modify viscosity. Phenolic novolac epoxies are used to produce vinyl esters with higher temperature capability and good solvent resistance, particularly in corrosive environments, and their FRP composites have demonstrated initial economy and better life cycle costs compared with metals. [Pg.299]

Brunstedt MR, Ziats NP, Robertson SP, Hiltner A, Anderson JM, Lodoen GA, et al. Protein adsorption to poly(ether urethane ureas) modified with acrylate and methacrylate polymer and copolymer additives. J Biomed Mater Res 1993 27(3) 367-77. [Pg.347]


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See also in sourсe #XX -- [ Pg.269 ]




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