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Poly -triol

Barrett, D.G., and M.N. Yousaf 2008. Poly(triol a-ketoglutarate) as biodegradable, chemoselective, and mechanically tunable elastomers. Macromolecules 41(17) 6347-6352. [Pg.48]

Scheme 8.31 Synthesis of the poly(triol a-ketoglutarate) bioelastomers from a-ketoglutaric acid and triols of glycerol, 1,2,4-butanetriol and 1,2,6-hexanetriol. Scheme 8.31 Synthesis of the poly(triol a-ketoglutarate) bioelastomers from a-ketoglutaric acid and triols of glycerol, 1,2,4-butanetriol and 1,2,6-hexanetriol.
Figure 8.16 Mass loss of the poly(triol a-ketoglutarate) bioelastomers such as PGa, PBa and PHa during degradation in phosphate buffer solutions (pH = 7.4, 37 °C) under the conditions of different curing temperature and time. Adapted from Barrett and Yousaf... Figure 8.16 Mass loss of the poly(triol a-ketoglutarate) bioelastomers such as PGa, PBa and PHa during degradation in phosphate buffer solutions (pH = 7.4, 37 °C) under the conditions of different curing temperature and time. Adapted from Barrett and Yousaf...
Polyurethane foams are formed by reaction with glycerol with poly(propylene oxide), sometimes capped with poly(ethylene oxide) groups with a reaction product of trimethylolpropane and propylene oxide or with other appropriate polyols. A typical reaction sequence is shown below, in which HO—R—OH represents the diol. If a triol is used, a cross-linked product is obtained. [Pg.190]

Crystalline polyesters are highly important as adhesive raw materials. They are normally crystalline waxes and are highly symmetrical in nature, which can aid the crystallization process [26]. Poly(hexamethylene adipate) and poly(caprolactone), shown in Table 2, are only two of the many crystallizable backbones. Poly(ethylene adipate) and poly(letramethylene adipate) are also commonly used in urethane adhesives. The crystalline polyesters are used in curing hot melts, waterborne polyurethanes, thermoplastic polyurethanes, and solvent-borne urethane adhesives. The adipates are available mostly as diols. The poly(caprolactones) are available as diols and triols. [Pg.770]

Liquid poly(caprolactone) triol — 540 MW Dibutyltin dilaurate catalyst — 0.001% by weight... [Pg.796]

Figure 1. Number fraction of ring structures per molecule (Nr) as a function of extent of reaction (p) for bulk, linear, and nonlinear polyurethane-forming reactions with approximately equimolar concentrations of reactive groups (r = [NCO]J [OH]0 ss 1) (2,3). Conditions O-linear polymerization, HDI + poly(ethyleneglycol) at 70°, [NCOfo — 5.111 mol/kg, [OH], = 5.188 mol/kg number-average number of bonds in chain forming smallest ring structure (v) = 25.2, and nonlinear polymerization, HDI and POP triol at 70°C, [NCO] — 0.9073 mol/kg, [OH]0 = 0.9173 mol/kg v = 115. Reproduced with permission from Ref. 5. Figure 1. Number fraction of ring structures per molecule (Nr) as a function of extent of reaction (p) for bulk, linear, and nonlinear polyurethane-forming reactions with approximately equimolar concentrations of reactive groups (r = [NCO]J [OH]0 ss 1) (2,3). Conditions O-linear polymerization, HDI + poly(ethyleneglycol) at 70°, [NCOfo — 5.111 mol/kg, [OH], = 5.188 mol/kg number-average number of bonds in chain forming smallest ring structure (v) = 25.2, and nonlinear polymerization, HDI and POP triol at 70°C, [NCO] — 0.9073 mol/kg, [OH]0 = 0.9173 mol/kg v = 115. Reproduced with permission from Ref. 5.
Studies have been made of the elastic (time-independent) properties of single-phase polyurethane elastomers, including those prepared from a diisocyanate, a triol, and a diol, such as dihydroxy-terminated poly (propylene oxide) (1,2), and also from dihydroxy-terminated polymers and a triisocyanate (3,4,5). In this paper, equilibrium stress-strain data for three polyurethane elastomers, carefully prepared and studied some years ago (6), are presented along with their shear moduli. For two of these elastomers, primarily, consideration is given to the contributions to the modulus of elastically active chains and topological interactions between such chains. Toward this end, the concentration of active chains, vc, is calculated from the sol fraction and the initial formulation which consisted of a diisocyanate, a triol, a dihydroxy-terminated polyether, and a small amount of monohydroxy polyether. As all active junctions are trifunctional, their concentration always... [Pg.419]

Figure 5.10 Dependence of the gel fraction, wg, on molar ratio of [OH]/[NCO] groups, ah, for poly(oxypropylene)triol (Niax LG 56)4,4 -diisocyanatodiphenyl-methane system. The dependence has been reconstructed from data of ref. [78]... Figure 5.10 Dependence of the gel fraction, wg, on molar ratio of [OH]/[NCO] groups, ah, for poly(oxypropylene)triol (Niax LG 56)4,4 -diisocyanatodiphenyl-methane system. The dependence has been reconstructed from data of ref. [78]...
Figure 7. Dependence on the gel fraction, molar ratio of OH to NCO groups, rjj, for poly(oxypropylene) (POP) triol -4,4 -diphenyl-methane diisocyanate (HDI) net-... Figure 7. Dependence on the gel fraction, molar ratio of OH to NCO groups, rjj, for poly(oxypropylene) (POP) triol -4,4 -diphenyl-methane diisocyanate (HDI) net-...
Diluent added during crosslinking has two main effects it Increases the population of elastically Inactive cycles and it weakens the interchain constraints. Studies of poly(oxypropylene) triol-diisocyanate networks in the presence of diluent have shown that the effect of diluent on the equilibrium modulus is much stronger than would correspond to the effect of cycles (Figure 10) (32) which again corroborates the concept of permanent interchain constraints. [Pg.16]

A synthetic approach to poly(ester-urethanes) was recently published by Xue et al. [48]. Glycerol was employed as a trifunctional initiator in the enzymatic ROP of CL. The three-arm PCL triol was then reacted with methylene-diphenyl diisocyanate (MDI) and hexanediol to yield a three-arm PCL-based poly(ester-urethane) with shape-memory properties. [Pg.92]

Polymerization To a 5 liter glass reactor was added hydroxymethylated fatty esters and 625 molecular weight poly (ethylene oxide) triol initiator in a 6 1 molar ratio. [Pg.383]

There are a number of inert binders such as polyester, epoxy, polysulfide, polyurethane which have been reported as binders for composite propellants and plastic bonded explosives (PBXs). At present, hydroxy-terminated polybutadiene (HTPB) is regarded as the state-of-the-art workhorse binder for such applications. However, the recent trend is to use energetic binders such as poly [3,3-bis(azidomethyl oxetane)] [poly(BAMO)], poly (3-azidomethyl-3-methyl oxetane) [poly(AMMO)], PNP, GAP diol and triol, nitrated HTPB(NHTPB), poly(NiMMO), poly(GlyN) and nitrated cyclodextrin polymers poly(CDN) for PBXs and composite propellants in order to get better performance. [Pg.115]

Type III poly(ortho esters) are very similar to the type I poly(ortho esters) in that they are based on a five member ortho ester ring (Heller et al. 1990). The linkages are quite different with the degradation process not forming a lactone, but an acid and a triol. Type III poly(ortho esters) developed to date are more hydrophilic... [Pg.292]

Figure 9 shows that the unsaturation of poly (propylene ether) diols and triols remained constant as the molecular weight was varied. By comparison, the unsaturation of commercial polyols (presumably made with potassium hydroxide) increased appreciably as the molecular weight increased. Figure 10 shows that upon varying the amount of diiso-... [Pg.237]

Crosslinked poly(ortho esters) are prepared by a reaction sequence in which an excess of the diketene acetal 3,9-bis(ethylidene 2,4,8,10-tetraoxaspiro [5,5] undecane) is reacted with a diol, and the ketene acetal terminated prepolymer is then crosslinked with a triol. Because the prepolymer is a viscous liquid at room temperature, the therapeutic agent and any excipients used are incorporated into the prepolymer by mixing at room temperature and then cured at temperatures that can be as low as 40°C. [Pg.174]

A method for extracting cadmium, copper, europium, and nickel metal ions from aqueous solution using modified polyethyleneimine is described. The polymer modification consists of grafting an imide, diol, triol, carboxylic acid, or thiocar-boxylic acid function to poly(ethyleneimine), which then forms stable metal complexes that are readily removed from solution. [Pg.683]

D 22 poly(caprolactone)triol exhibit sensitivity/selectivity... [Pg.317]


See other pages where Poly -triol is mentioned: [Pg.283]    [Pg.283]    [Pg.284]    [Pg.283]    [Pg.283]    [Pg.284]    [Pg.768]    [Pg.109]    [Pg.221]    [Pg.466]    [Pg.244]    [Pg.718]    [Pg.141]    [Pg.96]    [Pg.96]    [Pg.258]    [Pg.138]    [Pg.136]    [Pg.223]    [Pg.160]    [Pg.160]    [Pg.176]    [Pg.317]    [Pg.422]    [Pg.370]   
See also in sourсe #XX -- [ Pg.130 , Pg.131 ]

See also in sourсe #XX -- [ Pg.136 ]




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