Poly diol addition

Poly(propylene oxide) [25322-69-4] may be abbreviated PPO and copolymers of PO and ethylene oxide (EO) are referred to as EOPO. Diol poly(propylene oxide) is commonly referred to by the common name poly(propylene glycol) (PPG). Propylene oxide [75-56-9] and poly(propylene oxide) and its copolymers, with ethylene oxide, have by far the largest volume and importance in the polyurethane (PUR) and surfactant industry compared to all other polyepoxides. Articles reviewing propylene oxide (1), poly(propylene oxide) (2—4), other poly(aIkylene oxides) (4), and polyurethanes (5—7) are cited to lead the interested reader to additional detail not in the scope of this article. 

In addition, polyester polyols are made by the reaction of caprolactone with diols. Poly(caprolactone diols) are used in the manufacture of thermoplastic polyurethane elastomers with improved hydrolytic stabiHty (22). The hydrolytic stabiHty of the poly(caprolactone diol)-derived TPUs is comparable to TPUs based on the more expensive long-chain diol adipates (23). Polyether/polyester polyol hybrids are synthesized from low molecular weight polyester diols, which are extended with propylene oxide. 

Concerning the reaction of ACPC with diols, the frequent use of poly(ethylene glycol) has to be mentioned [20-24]. Ueda et al. ([22-24]) reacted preformed poly(ethylene glycol) (Mn between 6 x 10 to 2 x 10 ) with ACPC. In this case, unlike the reaction of ACPA with diols vide ante), no additional condensation agent was needed. The ethylene glycol-based thermally labile polymers were used to produce blocks with poly(vinyl chloride) [22], poly(styrene) [23], poly(methyl acrylate), poly(vinyl acetate), and poly(acrylonitrile) [24]. 

Poly(butylene terephthalate) (PBT), because of the addition of two methylene units in the diol-derived portion, has a lower melting point than PET with a Eg of about 170°C (structure 4.49). Moldability of aryl polyesters has been improved through the use of PBT instead of PET or by use of blends of PET and PBT. These aryl polyesters are used for bicycle wheels, springs, and blow-molded containers. 

Additional poly(ester-urethane) derivatives were prepared by reacting the step 1 prepolymer diol with selected diisocyanate as indicated below ... 

Figure 8 shows the characterization of these poly (propylene ether) diols by gel-permeation chromatography. There is a shift in the peak position to lower elution volumes, in accord with an increase in molecular weight with each monomer increment polymerized. The molecular-weight distributions of the three diols are similar and remain narrow after the addition of monomer increments. Since all of the molecules apparently continued to grow, this polymerization must proceed with very little chain termination under these conditions. 

The principle of miniemulsion polymerization to polyadditions of epoxyresins was successfully transferred to mixtures of different epoxides with varying diamines, dithiols, or diols which were heated to 60°C to form the respective polymers [125]. The requirement for the formulation of miniemulsions is that both components of the polyaddition reaction show a relatively low water solubility, at least one of them even below 10 5 g l1. The diepoxide bisphenol-A-diglycidylether was successfully used as epoxy component. In order to vary the obtained polymeric structure, tri- and tetra-functionalized epoxides were also used. As amino components a NH2 terminated poly(propylene oxide) with Mw=2032 g mol1, 4,4 -diaminobibenzyl, 1,12-diaminododecane, and 4,4 -di-aminodicyclohexylmethane were applied. As other addition components beside amine, 1,6-hexanedithiol and Bisphenol A were used. The hydrophobic compo-... 

The carboxyl group in acrylates and methacrylates can be esterified with various other alcohols, including diols such as ethylene glycol, diethyleneglycol, etc. In addition to the free acids and their esters, to this class can be added other derivatives of acrylic acid such as poly(acrylonitrile) [-CH2-CH(CN)-]n, poly(acrylamide) [-CH2-CH(CONH2)-]n,... 

Pyrolysis process for poly(2-hydroxyethyl methacrylate) occurs similarly to that for other methacrylic acid esters. The formation of 2-methyl-2-propenoic acid 2-hydroxyethyl ester, the monomer, shows that unzipping is a significant part of the process. Some other compounds in the pyrolysate also are generated from the polymer cleavage, such compounds including 2-methyl-2-propenoic acid ethenyl ester, propanoic acid, 2-methyl-2-propenoic acid, ethanol, etc. On the other hand, some compounds are not expected in the pyrolysate and they can be impurities or additives. Examples of such compounds are the hydrocarbons (undecene, dodecane, 1-dodecene, etc.), the esters of ethylene diol and the free 1,2-ethandiol, etc. The initiator AIBN and its decomposition products 2-methyl-2-propenenitrile and 2-methylpropanenitrile identified in the pyrolysate show that the polymer was obtained using AIBN as initiator. 

Poly(ortho esters) have also been produced by the addition of diols to diketene acetals (50). Principally because of ease of monomer synthesis, polymers were prepared by the addition of... 

The earlier example of the formation of a poly(urethane-co-urea) showed the change in properties made possible by including a comonomer (in that case a difunctional amine) together with the usual diol for reaction with a di-isocyanate. This can be extended to a wide range of step polymerizations where an additional reactant is added. Examples could be the use of two AB-type monomers (e.g. amino acids) or two AA (e.g. diacids) to react with one BB (a diamine) to form co-polyamides. Seveml features of step polymerization help in understanding the resultant copolymer. For example, since high-molar-mass polymer is formed only late in the reaction, the composition of the copolymer will be that of the feed ratio of the monomers. 

The single phase polyurethanes were obtained by first reacting a small amount of DAAB with MDI or TDI in DMF solution and subsequent addition of poly(tetramethylene adipate) diol, i. e., no EDA chain extender was used (13). 

In addition to PET, several other polyester systems have been evaluated for fiber use. Of these, only poly(cyclohexy1 diraethylene terephthalate) (PCHDT) appears to have achieved commercialization. The PCHDT may be prepared either by direct esterification or El processes with titanium alkoxide catalysts. The 1,4-bis(hydroxymethyl)cyclohexane, used as the diol in this polymer, is most commonly a mixture of cis and trans isomers in a ratio of approximately three to seven. Because of the greater steric requirements of the cyclohexyl ring, PCHDT has a higher viscosity and higher resilience than PET. It is also easier to dye. Its specific gravity is approximately 1.22 as compared to 1.38 for PET. 

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