Polypropylene polyol

Poly(phenylenethylene), dendronized, 522 Poly(phenylenevinylene) optically active, 510-511 synthesis of, 495-496 Poly(/ ara-phenylenevinylene)s, 472 Polypheny lquinoxaline (PPQ) hyperbranched, 312-314 synthesis of, 309-313 Polyphosphoric acid, 333 Polypropylene oxide) polyol, 223 Polypropylene polyols, 220 Poly (pyridine), synthesis of, 503-505 Polyquinoxaline (PQ), synthesis of, 309-313... 

In practice, toluene diisocyanate is used universally and the resin is usually a polypropylene polyol. For low density foams, the equivalent ratio of diisocyanate to polyol is normally higher than 1 1. Cross-linking is... 

SIM Simenido, A.V., Medved, Z.N., Denisova, L.L., Tarakanov, O.G., and Starikova, N.A., Some physicochemical properties of the mixtures of polypropylene polyols with water (Russ.), Vysokomol. Soedin., Ser. A, 21, 1727, 1979. 

This compound, designated Cyagard RF1204, has been recommended for use in polypropylene. Despite its high hydroxyl content, it is proposed not as a polyol but as a stable, high melting additive for polypropylene (108). 

TDA-derived polyols are made by alkoxylation. Polypropylene oxide adducts of I DA (14) and TDA-initiated polyether polyols (13,15) are used in rigid polyurethane foams and continue to be included in new formulations (62) as well as older appHcations. 

Aliphatic Glycidyl Ethers. Aliphatic epoxy resins have been synthesized by glycidylation of difunctional or polyfunctional polyols such as a 1,4-butanediol, 2,2-dimethyl-l,3-propanediol (neopentyl glycol), polypropylene glycols, glycerol, trimethylolpropane, and pentaerythritol. 

Meluch et al.10 reported that high-pressure steam hydrolyzes flexible polyurethane foams rapidly at temperatures of 232-316°C. The diamines are distilled and extracted from the steam and the polyols are isolated from the hydrolysis residue. Good results were obtained by using reclaimed polyol in flexible-foam recipes at file 5% level. Mahoney et al.53 reported the reaction of polyurethane foams with superheated water at 200°C for 15 min to form toluene diamines and polypropylene oxide. Gerlock et al.54 studied the mechanism and kinetics of the reaction... 

After 8 h of reaction, the reactor was allowed to cool. A two-layer liquid formed. The top layer was found to contain mostly polypropylene ether triols with about 20% by weight diethylene glycol and 5% by weight toluene diamines. The top layer was purified by vacuum distillation at 2 mm Hg and 200° C to produce 320 g of a light brown liquid residue. This residue (polyols) was used as a replacement for 5% by weight of the Pluracol 535 polyol in the formulation of a flexible polyurethane foam. A flexible foam which had good resiliency and a density of 2.2 Ib/ft3 was obtained. At higher replacement levels, lesser quality foams were obtained. 

Acid-treated clay catalyst Engelhard F-24 was found to be very effective for the alkylation of diphenylamine (DPA) with an olefin such as a-methyl styrene (AMS) to obtain a mixture of mono and dialkylated diphenylamines (Chitnis and Sharma, 1995). For example, alkylation of DPA with AMS produced a mixture of 4-(a,a-dimethyl benzyl) diphenylamine, i.e. monocumyl-diphenylamine (MCDPA) and 4,4 -bis(a,a-dimethylbenzyl) diphenylamine, i.e. dicumyldiphenylamine (DCDPA) (Eqn.(l 1)). The dialkylated diphenylamine, i.e. DCDPA, is indu.strially important as an antioxidant and heat stabilizer. DCDPA is reported to be an ideal antioxidant for many materials like polyethylene, polypropylene, polyether polyol, polyacetals, nylon 6, synthetic lubricants, hot melt adhesives, etc. 

Polypropylene ether) polyol is the single most important product from propylene oxide and enjoys a predominant position in polyurethane applications. The ether linkages are very abundant in these polyols and they contribute to the physical and chemical properties in many applications such as surfactant action and hydrogen-bond formation. 

Figure 9. Unsaturation vs. molecular weight for polypropylene ether) polyols made with Zns[Co(CN)6]2 glyme ZnCh and made commercially...

Nonionic Surface-Active Agents. Approximately 14% of the ethylene oxide consumed in the United States is used in the manufacture of nonionic surfactants. These are derived by addition of ethylene oxide to fatty alcohols, alkylphenols (qv), tall oil, alkyl mercaptans, and various polyols such as polypropylene glycol), sorbitol, mannitol, and cellulose. They are used in household detergent formulations, industrial surfactant applications, in emulsion polymerization, textiles, paper manufacturing and recycling, and for many other applications (281). 

To improve the low temperature properties, a different backbone needs to be used. A mixture of polyethylene and polypropylene adipates has been found to be suitable. The physical properties are not as good as with the single polyol. 

PPDI PPG Prepolymer Processability initiating agent. An abbreviation for paraphenylene diisocyanate. Polypropylene glycol. The product from reacting a polyol with an isocyanate. The relative ease with which a raw or compounded polymer can be handled. 

Polyesters make tough and wear-resistant urethanes. The one major drawback is the hydrolysis at the ester grouping. The hydrolysis can either be acid or alkali promoted. In more neutral conditions, the major breakdown product is normally adipic acid that catalyses further attack. The normal approach is to use carbodiimides to block further breakdown. Polyols made using polypropylene carbonate produce polyurethanes with polyester characteristics but with enhanced hydrolysis resistance. 

These materials were introduced by Wyandotte Chemicals Corp and are made by the sequential addition of propylene oxide and ethylene oxide to a low molecular weight reactive hydrogen compound [31]. The polypropylene oxide mid-block is water insoluble and acts as the hydrophobic part of the molecule in the same way as fatty alcohol in conventional ethoxylates. The addition of ethylene oxide to polypropylene oxide mid-block gives water soluble polyols having surface-active properties and the structure ... 

Long-chain polyether polyols, such as polypropylene glycol, when reacted with epichlorohydrin produce a diepoxy resin with an internal polyether chain that serves both to... 

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