Dimer diol

Powder coatings are formulated from the reaction product of trimethylolpropane and IPDI, blocked with caprolactam, and polyester polyols. The saturated polyester polyols are based on aromatic acid diols, neopentyl glycol, and trimellitic anhydride for further branching. To avoid the release of caprolactam in the curing reaction, systems based on IPDI dimer diols are used. 

Industrial Development and Application of Biobased Oleochemicals 4.4.1.1 Dimer Diols Based on Dimer Acid [11, 12]... 

Owing to their improved stability towards hydrolysis and oxidation, dimer diol polyethers (and dimer diol polycarbonates) are used as soft segments in the preparation of thermoplastic polyurethanes. Polyurethanes prepared from such oleo-chemical building blocks are very hydrophobic and show the expected stability. 

Dimer and trimer alcohols introduced into the structure of PU confer on them very high hydrophobicity, water repellency, flexibility and chemical stability. The polyester urethanes based on dimeric diols and dimeric acids are the most hydrolysis resistant polyester urethanes known so far [73]. 

Soy Oil Systems successfully developed new polyols based on soybean oil oxidation (oxygen blown oils). Many other companies and research centres are involved in serious research on the valorification of natural renewable resources by transforming them into polyols and into PU. Very important research on unsaturated vegetable oil, chemical transformation into polyols for PU were developed in Pittsburg State University, Kansas (under Professor Zoran Petrovic), Henkel and Cognis (Sovermol polyols), Unichema (dimer acids and dimer diols etc.), Bayer, Cargill and other companies. 

Polyesterpolyols based on dimer acids or dimer diol have been largely used in sol-vent-borne and water-based coating applications including alkyd resins and aqueous polyurethane dispersions. ... 

Dimer acids and their derivatives, dimer diol and dimethyldimerate, are long-chain polymer grade fatty acids which act as good modifiers for condensation polymers. High amounts of aromatic structure and linear structure increase hardness and impact properties, respectively. They can be used to modify... 

Polyesters or polyamides fi om unsaturated fatty acids diamines or dimer diol-based glycols... 

Motivated by the desirable lubricant-related properties obtained for diol diesters of pHAs discussed above and the desirable properties (low pour point and high VI) and biodegradability of polyol-fatty acid ester lubricants (26,44-46), star polymers consisting of a polyol core [e.g., pentaerythritol (PE), trimethylolpropane (TMP), or dimer diol (DD)] and pRA arms (Figure 1) were synthesized in bulk at 70°C using CAL as biocatalyst in our laboratory within a 1-week period. DD is a biolubricant material derived chemically from unsaturated fatty acids. 

The Diels-Alder reaction is also involved in the synthesis of dimer acid from oleic acid or plant oils. Dimer acids typically consist of a broad distribution of highly branched 36-carbon dicarboxylic acids that contain cyclohexene groups. They are formed using clay catalysts at a temperature above 200°C, and are manufactured worldwide for employment in polyamide resins (Breuer, 2007 Heidbreder et al, 1999). The hydrogenation of dimer acids yields dimer diols, which are useful as polyols in the preparation of polyurethanes (Heidbreder et al., 1999). 

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