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Polycaprolactone termination

Polybutadienes, polycaprolactones, polycarbonates, and amine-terminated polyethers (ATPEs) are shown in Scheme 4.4 as examples of other commercially available polyols. They are all specialty materials, used in situations where specific property profiles are required. For example, ATPEs are utilized in spray-applied elastomers where fast-reacting, high-molecular-weight polyamines give quick gel times and rapid viscosity buildup. Polycarbonates are used for implantation devices because polyuredtanes based on them perform best in this very demanding environment. Polycaprolactones and polybutadienes may be chosen for applications which require exceptional light stability, hydrolysis resistance, and/or low-temperature flexibility. [Pg.213]

See also PBT degradation structure and properties of, 44-46 synthesis of, 106, 191 Polycaprolactam (PCA), 530, 541 Poly(e-caprolactone) (CAPA, PCL), 28, 42, 86. See also PCL degradation OH-terminated, 98-99 Polycaprolactones, 213 Poly(carbo[dimethyl]silane)s, 450, 451 Polycarbonate glycols, 207 Polycarbonate-polysulfone block copolymer, 360 Polycarbonates, 213 chemical structure of, 5 Polycarbosilanes, 450-456 Poly(chlorocarbosilanes), 454 Polycondensations, 57, 100 Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT), 25 Polydimethyl siloxanes, 4 Poly(dioxanone) (PDO), 27 Poly (4,4 -dipheny lpheny lpho sphine oxide) (PAPO), 347 Polydispersity, 57 Polydispersity index, 444 Poly(D-lactic acid) (PDLA), 41 Poly(DL-lactic acid) (PDLLA), 42 Polyester amides, 18 Polyester-based networks, 58-60 Polyester carbonates, 18 Polyester-ether block copolymers, 20 Polyester-ethers, 26... [Pg.595]

Surfactants are prepared which contain carboxylic acid ester or amide chains and terminal acid groups selected from phosphoric acid, carboxymethyl, sulfuric acid, sulfonic acid, and phosphonic acid. These surfactants can be obtained by reaction of phosphoric acid or phosphorus pentoxide with polyhydroxystearic acid or polycaprolactone at 180-190°C under an inert gas. They are useful as polymerization catalysts and as dispersing agents for fuel, diesel, and paraffin oils [69]. [Pg.565]

Preparation and characteristics of ABA type polycaprolactone-b-polydimethyl-siloxane block copolymers have been recently reported 289). In this study, ring-opening polymerization of e-caprolactone was achieved in melt, using a hydroxybutyl terminated PSX as the initiator and a catalytic amount of stannous octoate. Reactions were completed in two steps as shown in Reaction Scheme XIX. [Pg.51]

There are various routes to vinyl macromonomers [Gnanou and Taton, 2002]. For example, the reaction of an HO-terminated polymer such as polysiloxane, polycaprolactone, or poly-tetrahydrofuran with acryloyl chloride... [Pg.753]

Composite rocket propellants are two-phase mixtures comprising a crystalline oxidizer in a polymeric fuel/binder matrix. The oxidizer is a finely-dispersed powder of ammonium perchlorate which is suspended in a fuel. The fuel is a plasticized polymeric material which may have rubbery properties (i.e. hydroxy-terminated polybutadiene crosslinked with a diisocyanate) or plastic properties (i.e. polycaprolactone). Composite rocket propellants can be either extruded or cast depending on the type of fuel employed. For composite propellants which are plastic in nature, the technique of extrusion is employed, whereas for composite propellants which are rubbery, cast or extruded techniques are used. [Pg.155]

Figure 7.7 SAXS profiles for two hydroxyl-terminated oligomers crosslinked by alkoxysilane sol-gel chemistry. First, 1 mole of macrodiol, SS (hydrogenated polybutadiene, HPBD or polycaprolactone, PCL, Mn= 2 kg mol-1), was reacted at 80°C with 2 mole of dicyclohexylmethane diisocyanate, H12 MDI. After complete reaction, the prepolymer was dissolved in tetrahydro-furan and the y-aminosilane, yAPS was added dropwise at room temperature. After 1 h of reaction, the solvent was removed under pressure. The final network was obtained in the absence of a solvent by hydrolysis and condensation of the ethoxysilane groups by the addition of 0.1 mol% TFA, trifluor-oacetic acid. After stirring at room temperature, the mixture was cast into a mold and cured for 24 h at 100°C under pressure, and then postcured at 150°C for 12 h. (Cuney et al., 1997 - Copyright 2001, Reprinted by permission of John Wiley Sons, Inc.)... Figure 7.7 SAXS profiles for two hydroxyl-terminated oligomers crosslinked by alkoxysilane sol-gel chemistry. First, 1 mole of macrodiol, SS (hydrogenated polybutadiene, HPBD or polycaprolactone, PCL, Mn= 2 kg mol-1), was reacted at 80°C with 2 mole of dicyclohexylmethane diisocyanate, H12 MDI. After complete reaction, the prepolymer was dissolved in tetrahydro-furan and the y-aminosilane, yAPS was added dropwise at room temperature. After 1 h of reaction, the solvent was removed under pressure. The final network was obtained in the absence of a solvent by hydrolysis and condensation of the ethoxysilane groups by the addition of 0.1 mol% TFA, trifluor-oacetic acid. After stirring at room temperature, the mixture was cast into a mold and cured for 24 h at 100°C under pressure, and then postcured at 150°C for 12 h. (Cuney et al., 1997 - Copyright 2001, Reprinted by permission of John Wiley Sons, Inc.)...
Preparation of Cast Elastomers. The cast elastomers were prepared in a two-step procedure. First prepolymers were made from one polyether polyol (poly(oxy-tetramethylene) glycol of 1000 M.W., (POTMG)) and two polyester polyols (adipate polyester of 2000 M.W. (PAG) and polycaprolactone of 1250 M.W. (PCL)) by reaction with the corresponding diisocyanates (MDI, PPDI, CHDI or NDI) at an NCO/OH ratio of 2/1. The temperature was maintained at 80°C and periodic samples were withdrawn to determined the isocyanate content. When the isocyanate content of the mixture reached within 0.3% of the calculated value, the reaction was stopped by cooling. The prepolymer could be kept for a period of six months in the absence of moisture. The isocyanate-terminated prepolymers were then chain-extended with... [Pg.420]

Some other specialised polyester polyols, like polycarbonate and polycaprolactone, possess superior hydrolytic resistance. Aliphatic polyhydrocarbon polyol such as hydroxyl terminated polybutadiene (HTPB), is advantageous in many respects. These substances are resistant to acidic or basic hydrolysis, possess good adhesion and can be used where low polarity and good electrical insulation are required. [Pg.151]

Polycaprolactone (Mn = 4000 and 37,000). Methoxy and hydroxy terminated polymer chains CO2 evolution, weight loss, and molecular weight Compost inoculum Actinomycetes species isolated from compost [111]... [Pg.958]

Dispersions can also be made by solvent-free processes. For example, isophorone diisocyanate, polycaprolactone diol, polytetrahydrofiirandiol, and dimethylolpropionic acid are reacted with an NCO OH ratio of 1.6 1 to make an isocyanate-terminated prepolymer. The prepolymer is neutralized with triethy-lamine and dispersed in water. The prepolymer is then chain extended by reacting with hydrazine hydrate. [Pg.8695]

The important assumptions in the derivation of this terminal diameter contain uniform electric fleld. There is no phase change and no inelastic stretching of the jet. The experimental research showed that this model can be qualitatively valid for selected polymeric solutions including polyethylene oxide (PEO) and polycaprolactone (PCL) in low concentrations [17,58-59]. [Pg.299]

A surface-initiated enzymatic ROP has also been reported, whereby CL and DXO were grafted from hydroxyl-terminated self-assembled monolayers (SAMs) on gold, using Novozym 435 [117], while polycaprolactone-modified hydroxyethylcel-lulose films were prepared by the enzymatic ROP of CL [118]. [Pg.393]


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See also in sourсe #XX -- [ Pg.77 , Pg.78 ]




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