Polyol Analysis

For both polyethers and polyesters that are to be utilized for polyurethane formation the acid and hydroxyl content are of prime concern, as in formulating for polyurethane applications all active hydrogens that take part in the urethane reaction need to be known as accurately as possible. Unless these variables can be closely controlled, accurate NCO/OH ratios will not be possible and it will prove difficult to manufacture polyurethanes of consistent quality. 

Additionally, polyesters and polyethers may contain several impurities derived from their methods of manufacture and being polymeric materials may vary in molecular weight and type of end-group. For routine analysis of raw materials, a determination of hydroxyl value, acid value and water content is usually sufficient. The reactivity of polyesters of the same chemical type can vary widely and for this reason it is sensible that an activity test be performed similar to that for diisocyanates using a diisocyanate of standardized activity. 

Chemically identical polyesters can vary widely in hydrolytic stability. This is most probably due to trace catalysts in routine testing it is easier to perform an empirical hydrolysis test rather than do a full chemical analysis. 

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An amine-terminated poly ether (ATPE) is prepared as follows. Charge poly(tetramethylene oxide) diol (PolyTHF 1000, BASF, 75.96 g, 0.0759 m) to a 500-mL three-neck round-bottom flask fitted with a thermocouple, a mechanical stirrer, and a vacuum port. Add tert-butylacetoacetate (24.04 g, 0.1582 m) and apply vacuum. Heat at 175° C for 4 h, Fourier transform infrared (FTIR) analysis should indicate complete loss of the polyol OH absorption at 3300 cm. The room temperature viscosity of the product should be about 520 mPa-s. React this acetoacetylated product (85.5 g, 0.0649 m) with cyclohexylamine (14.5 g, 0.1465 m) at 110° C under vacuum for several hours. Cool the resultant cyclohexylaminocrotonate poly ether product to room temperature (1790 mPa-s at room temperature). 

Example 5. Glycolysis of Polyurethanes with Propylene Oxide after Pretreatment with Ethanolamine.55 A rigid polyurethane foam (ca. 100 g) was dissolved in 30 g ethanolamine by heating. Excess ethanolamine was stripped, leaving a clear solution. Infrared and GPC analysis indicated that the clear solution obtained contained some residual polyurethane, aromatic polyurea, aliphatic polyols, aromatic amines, and N,N -bis(f -hydroxyethyljurea. Next the mixture was dissolved in 45 g propylene oxide and heated at 120°C in an autoclave for 2 h. The pressure increased to 40 psi and then fell to 30 psi at the end of the 2-h heating period. The product was a brown oil with a hydroxyl number of485. 

In polymer applications derivatives of oils and fats, such as epoxides, polyols and dimerizations products based on unsaturated fatty acids, are used as plastic additives or components for composites or polymers like polyamides and polyurethanes. In the lubricant sector oleochemically-based fatty acid esters have proved to be powerful alternatives to conventional mineral oil products. For home and personal care applications a wide range of products, such as surfactants, emulsifiers, emollients and waxes, based on vegetable oil derivatives has provided extraordinary performance benefits to the end-customer. Selected products, such as the anionic surfactant fatty alcohol sulfate have been investigated thoroughly with regard to their environmental impact compared with petrochemical based products by life-cycle analysis. Other product examples include carbohydrate-based surfactants as well as oleochemical based emulsifiers, waxes and emollients. 

Analysis of the Isocyanate was accomplished by performing an amine equivalent determination (per ASTM D1638). The polyol component was analyzed for hydroxol equivalent by an acetylation procedure developed at Sandla National Laboratories. An 0.8 gram sample Is acetylated with a 1/9 acetic anhydrlde-pyrldlne mixture for 2 hours at reflux temperature and then the free acetic acid Is back titrated with base and compared to a blank. From this Information a hydroxol equivalent can be calculated. The polyol acid number was determined by ASTH D2849. 

Thus, a multibiomarker tracer analysis of both water-soluble and hydrophobic organic compounds in various environmental samples using the GC-MS analytical method is useful. The saccharides, i.e. monosaccharides, disaccharides, anhydrosaccharides, and polyols (reduced sugars) are an important class of water-soluble compounds to be considered as environmental tracers. 

BASF has published the results of a Life-Cycle Analysis environmental study of the commercial manufacturing process for Lupranol Balance 50 polyol [151]. The study indicates a positive trend on the environmental impact of manufacturing the polyols by the new process. The actual impact of the current offering is difficult to gauge fi om this study, since in some cases the theoretical improvements... 

As renewable raw materials began to enter the marketplace, it was inevitable that claims to the level of renewable content in commercial offerings would become an issue of public debate. As previously pointed out in this article, some renewable raw materials have been common to the polyol chemistry for many decades, so claims to at least some renewable content are justified. Because the commercialization of different renewable polyol chemistries has created a highly competitive environment, some scientists in the field have promoted a method for the independent verification of the renewable sourced carbon in the final product [153]. ASTM International has published a concise and informative briefing paper on the method development for the determination of renewable carbon content in carbon-containing substances [154]. The method involves the analysis of content in the finished polyurethane products via radiocarbon dating [155]. The technique is fast and accurate, and has become commonly available by contract analysis through independent analytical laboratories [156]. 

The preparative method used for the polyol allowed a reduction in the competitive oligomerization of the polyol, resulting in a relatively lower amount of oligomeric polyol, seen when the GPC analysis is compared to that of the blown oil polyol (Fig. 10). An idealized structure of the polyol, along with a GPC analysis is represented in Fig. 23. 

Helling R (2006) Life cycle analysis of polyols from soy oil or castor oil. In Proceedings AlChE 2006, Topical Session 4 Sustainable Biorefineries, 16 November 2006, San Francisco. AlChE, New York... 

Polyols too are important in the wine industry, as glycerol is related to the sensory characteristic of smoothness, while inositol is used as a purity parameter for concentrated rectified musts [47], Analysis of sugars is carried out in cider production [48],... 

Table 9.2.2 Chemical Analysis (wt%) of Some Noble Metal Powders Obtained by the Polyol Process...

Table 9.2.4 Chemical Analysis of Two Cobalt Powders Obtained from the Same Parent Hydroxide by Solid-Gas Reduction and by the Polyol Process (Main Impurities/ Cobalt Ratios in ppm by Weight)...

Determination of NG by Gas Liquid Chromatography. This technique is useful for measuring NG or other polyol nitrates present in air. Bubble a 10-liter sample thro two 10-ml containers of ale, then inject some of the ale soln onto a siliconized Chromosorb P column coated with 10% Igepal CO-880. Run the analysis at 160° under nitrogen carrier to detect a min of 2mg (Ref 14)... 

A random urine sample can be used for the analysis of polyols. TALDO and RPI deficiencies, as well as galactosaemia and presumably sorbitol dehydrogenase deficiency, can be diagnosed using urine. The samples are stored frozen. Repeated freeze-thawing does not influence the concentrations of the polyols. 

Wamelink MM, Smith DE, Jakobs C, Verhoeven NM (2005) Analysis of polyols in urine by liquid chromatography-tandem mass spectrometry a useful tool for recognition of inborn errors affecting polyol metabolism. J Inherit Metab Dis 28 951-963... 

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