Polyethylene glycol/polyurethane copolymer

In our work, we calculate the equilibrium moisture from the dry and saturated mass of samples. The method was described by Thomson. We use more hydrophilic polyols, for example, hydrophiUc polyurethanes and polyethylene glycol homopolymers are used. More commonly, however, we will be using polyols from the Pluronic series of block copolymers discussed in Chapter 2. 

Polyethylene glycol (PEG) and the very similar polyethylene oxide (PEO) are used as biocompatible coating agents and hydrogel forming materials, often as block or graft copolymers with other materials (Eig. IF). They are often bound to polyurethanes to form hydrophilic foams such as Biopol (Metabolix Inc.). 

Polyethylene glycol (PEG) is another well-known molecule used to reduce protein adsorption and/or platelet adhesion. Surface enrichment of a triblock oligomeric PEG containing additive from a polyurethane matrix was reported [54,55]. The authors used PEG as the active groups to suppress protein and platelet adhesion. The authors first synthesized a methylene diphenyl diisocyanate (MDI)-poly (tetramethylene oxide) (PTMO) 1000 prepolymer with a MW of approximately 4750 (PU4750), and then this prepolymer was terminally functionalized with mono amino-polyethylene oxide (PEG) with different MW (PEO550, 2000, or 5000, Table 2.3). This triblock copolymer was mixed with a polyurethane (MDI/ PTMO 1000/ethylene diamine (ED)) at different ratios in dimethylformamide (DMF) and cast into polymer films. The surface compositions of these films were evaluated by XPS. 

In the copolyesterification with EG, it was found that PIE was incorporated in the recovered polymer in greater relative quantities than was EG. This was also the case with polyethylene glycol. The poly(ether-ester) block copolymer had better solubility properties in common organic solvents than the homopolyesters. The polyurethanes gave higher molecular weights than did the polyesters. 

Tg measurements have been performed on many other polymers and copolymers including phenol bark resins [71], PS [72-74], p-nitrobenzene substituted polymethacrylates [75], PC [76], polyimines [77], polyurethanes (PU) [78], Novolac resins [71], polyisoprene, polybutadiene, polychloroprene, nitrile rubber, ethylene-propylene-diene terpolymer and butyl rubber [79], bisphenol-A epoxy diacrylate-trimethylolpropane triacrylate [80], mono and dipolyphosphazenes [81], polyethylene glycol-polylactic acid entrapment polymers [82], polyether nitrile copolymers [83], polyacrylate-polyoxyethylene grafts [84], Novolak type thermosets [71], polyester carbonates [85], polyethylene naphthalene, 2,6, dicarboxylate [86], PET-polyethylene 2,6-naphthalone carboxylate blends [87], a-phenyl substituted aromatic-aliphatic polyamides [88], sodium acrylate-methyl methacrylate multiblock copolymers [89], telechelic sulfonate polyester ionomers [90], aromatic polyamides [91], polyimides [91], 4,4"-bis(4-oxyphenoxy)benzophenone diglycidyl ether - 3,4 epoxycyclohexyl methyl 3,4 epoxy cyclohexane carboxylate blends [92], PET [93], polyhydroxybutyrate [94], polyetherimides [95], macrocyclic aromatic disulfide oligomers [96], acrylics [97], PU urea elastomers [97], glass reinforced epoxy resin composites [98], PVOH [99], polymethyl methacrylate-N-phenyl maleimide, styrene copolymers [100], chiral... 

The application of AFM to surface morphological studies has been covered in relation to the following polymers polyesters, polyethylene (PE), polystyrene (PS) [28], polycarbonate, polyimide, polytetrafuoroethylene (PTFE) [29], polyurethane (PU) [30], rubbers [31], polyethylene glycol (PEG) [32], PS and poly(N-butyl-methacrylate) [33], PS [34], PP [35, 36], polyethers [37], polyorthoesters [38], poly(p-phenylene-vinylene) [39], bisphenol A-1, 8-dibromooctane copolymer [40], polycatechol [41], polyethylene terephthalate (PET) [42], poly(p-dioxanone)-poly(epsilon caprolactone) [43], poly(L-lactide-polyethylene glycol) [44] and polyvinylidene fluoride [45]. 

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