Poly ether polyol

The frothing system was prepared as follows. 96 parts of sucrose-based poly ether polyol (OH No. 460), 60 parts of trichloromonofluoro-methane, 120 parts of tris(chloroethyl) phosphate, 20 parts of silicone... 

ASTM D 4273-83 (1988) Standard Methods for Testing Polyurethane Raw Materials Determination of Primary Hydroxyl Content of Poly ether Polyols, 9 pp (Comm D-20)... 

Naugard PS-30 is a liquid amine antioxidant typically used with phenolic antioxidants, phosphites, and synergists in poly-ether polyols to inhibit physical/color scorch associated with the production of flexible urethane foam. 

Figure 1.2 shows the world consumption of poly ether polyols and polyester polyols for polyurethanes in the period of time 2000-2004. 

For poly ether polyols an NMR method was elaborated for functionality determination [20]. The most usual and practical method for functionality determination is based on the assessment of the MW of an oligo-polyol, by a method applicable to low MW compounds (MW < 10,000 daltons), such as vapour pressure osmometry (VPO) or gel permeation chromatography (GPC), together with hydroxyl number determination. The functionality is calculated by using the fundamental equation 3.4 ... 

The 19fluorine NMR method is one of the most accurate methods for primary hydroxyl determination. It is suitable for oligo-polyols (especially poly ether polyols) with hydroxyl numbers in the range 24-300 mg KOH/g and primary hydroxyl percentages in the range of 2 to 98%. 

Polyalkylene oxide polyether polyols are the most important group of polyols for PU, representing around 80% of the total oligo-polyols production. The general formula of a polyalkylene oxide poly ether polyol is presented in Figure 4.3. 

Figure 4.33 General technological flow for poly ether polyol fabrication by anionic...

The creation of the autocatalytic high MW aminic polyols based on N-methyl substituted poly amines, represents an important development in the area of poly ether polyols for low-fogging flexible PU foams. The VORANOL VORACTIV polyols developed by DOW represent a revolutionary group of autocatalytic polyols with reduced volatile organic compounds (VOC) emissions in PU products, especially in high resilience foams for bedding and automotive seating [149, 150]. 

Synthesis of High Molecular Weight Poly ether Polyols. .. 

The superior characteristics of polyester polyol based polyurethanes are explained by a better crystalline structure [1, 7] in the urethane segment, compared to the majority of poly ether polyols which are amorphous [except polytetrahydrofuran (PTHF)], due to the superior secondary forces between the polyester chains [8] and also due to a superior thermal and fire resistance, compared to polyether polyol based polyurethanes. Polyester-based polyurethanes (flexible foams, coatings), have a superior solvent resistance compared to the polyether-based polyurethanes [8]. 

In Chapter 3, the chemistry and technology of the most important oligo-polyols used for elastic polyurethanes fabrication, in fact high MW oligomers (2000-12000 daltons) with terminal hydroxyl groups and low functionality (2-4 hydroxyl groups/mol) were discussed. Polyalkylene oxide polyols (homopolymers of PO or copolymers PO - EO, random or block copolymers), polytetrahydrofuran polyols, filled polyols (graft poly ether polyols, poly Harnstoff dispersion - polyurea dispersions (PHD) and polyisocyanate poly addition (PIPA) polyols), polybutadiene polyols and polysiloxane polyols were all discussed. The elastic polyurethanes represent around 72% of the total polyurethanes produced worldwide. 

A very interesting catalyst used in the synthesis of polyether polyols for rigid PU foams is urea [41]. Sucrose poly ether polyols obtained in the presence of urea as catalyst have a very light colour [41]. Unfortunately with urea it is possible to obtain lower molecular weight polyether polyols, with an hydroxyl number (OH ) higher than 500 mg KOH/g. 

By solubilisation of propoxylated bisphenol A with the structure 15.28, in a sucrose-based polyether polyol for rigid foams, an homogeneous mixture is obtained [29]. The viscosities of these mixtures increase with the content of propoxylated bisphenol A. From these mixtures rigid PU foams were obtained. Due to the aromaticity introduced by the propoxylated bisphenol A, the physico-mechanical properties of the resulting rigid PU foams were superior to the rigid PU foams made with the sucrose-based poly ether polyol alone [29]. 

By hydrolysing a polyether PU, a polyether polyol is obtained with a similar structure to those of the initial virgin poly ether polyol. For polyester PU the hydrolysis reaction is more complicated because the esteric groups of polyesters are hydrolysed back to monomers, such as diacids and glycols or polyols (reaction 20.3). 

Water-blown low density rigid polyurethane foams have been prepared with poly(ether polyol)s, polymeric isocyanates, DSF, water, a catalyst mixture, and a surfactant the immiscible character of the blend composites. Soy flour and the initial water content were varied from 0 to 40 per cent and from 4.5 to 5.5 per cent of the poly(ether polyol) content, respectively. The addition of soy flour in the rigid polyurethane foam system contributed to a higher glass transition temperature, and increasing the initial water content also resulted in an increase in the glass transition temperature [85]. 

Poly ether polyols. The formation of polyether polyols is commercially the most important reaction of PO. A polyol is the product of reaction of an epoxide and compounds or initiators (e.g., glycols amines, acids, or water), which contain active hydrogen. 

Polyureas. Polyureas involve the combination of novel MDI polymers and either amine or imino-functional poly ether polyols. The resin systems can be reinforced with milled glass fibers, flaked glass, Wollastanite, or treated mica, depending on the compound requirements as too processability or final product. 

Internal mold release agents bleed to the surface of the molded article. Some of these articles cannot be painted even after appropriate preparation steps for painting has been done. Others are incompatible with poly ether polyols. Most of them seriously reduce the activity of the catalyst. Almost all show degradation of physical properties, such as reduced elongation. ... 

Chemistry of Polyurethane Adhesives and Sealants 115 Table 6 Common initiators for poly ether polyols. 

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