Abstract:
Using novel synthetic techniques, siloxane-urea segmented copolymers are made. The copolymers advantageously contain a polyether interface, with controlled morphologies and properties. High molecular weight, high strength siloxane-urea copolymers with a high content of urea hard segment may be prepared. Polymer properties that can independently be controlled include modulus, ultimate tensile strength, level of equilibrium water absorption and refractive index.
Abstract:
Using novel synthetic techniques, siloxane-urea segmented copolymers are made. The copolymers advantageously contain a polyether interface, with controlled morphologies and properties. High molecular weight, high strength siloxane-urea copolymers with urea hard segment contents ranging from 5 to over 60% by weight may be prepared. Polymer properties that can independently be controlled include modulus (1.0 to 120 MPa), ultimate tensile strength (1.5 to 25 MPa), level of equilibrium water absorption (˜0 to 100% by weight) and refractive index (1.43 to 1.46).
Abstract:
Using novel synthetic techniques, siloxane-urea segmented copolymers are made. The copolymers advantageously contain a polyether interface, with controlled morphologies and properties. High molecular weight, high strength siloxane-urea copolymers with urea hard segment contents ranging from 5 to over 60% by weight may be prepared. Polymer properties that can independently be controlled include modulus (1.0 to 120 MPa), ultimate tensile strength (1.5 to 25 MPa), level of equilibrium water absorption (˜0 to 100% by weight) and refractive index (1.43 to 1.46).
Abstract:
Novel segmented polyurethaneurea copolymers were synthesized using a poly(ethylene-butylene)glycol based soft segment. Dynamic mechanical analysis (DMA), small angle X-ray scattering (SAXS) and atomic force microscopy (AFM) established the presence of a microphase-separated structure in which hard microdomains are dispersed throughout a soft segment matrix. Wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) results suggest the materials are amorphous. Samples that are made with HMDI/DY and have hard segment contents in the range of 16-23 wt % surprisingly exhibit near-linear mechanical deformation behavior in excess of 600% elongation. They also show very high levels of recoverability even though their hysteresis is also considerable. The materials are both melt processable and solution processable.
Abstract:
A new family of triblock (A-B-A type) thermoplastic, polyurethane, polyurethaneurea, polyurea and polyamide copolymers has been prepared. (A) blocks represent the hard segments, such as urethane, urea, urethaneurea or amide type segments. (B) blocks represent the soft segments, such as aliphatic polyethers, aliphatic polyesters, polydimethylsiloxanes, polyalkanes or their copolymers. These novel material display very interesting microphase morphologies, mechanical properties, solubility characteristics and melt behavior.
Abstract:
A segmented copolymer can be produced without needing a chain extender. The conventional view that a chain extender was needed to construct a segmnented copolymer has been disproven. For example, by certain reactions of a diisocyanate with oligomeric and polymeric diols or diamines, segmented copolymers can be produced without needing a chain extender. Segmented copolymers not containing ethylene glycol, 1,4-butanediol and ethylene diamine can be produced.
Abstract:
A water vapor-permeable, waterproof adhesive polymer and a linear polyurethane-urea polymer, are utilized to coat various textile materials. The compositions of these polymers as well as various methods of coating the textile materials are described.