Oligo-polyols structure, and polyurethane propertie

Relationships Between the Oligo-Polyol Structure and Polyurethane Properties... 

All the previous information regarding the general chemistry of polyurethanes and the structure of isocyanates have a role in the better understanding of how the oligo-polyols get chemically inserted in the high MW polyurethane structure and to understand the role played by the polyol structure in the properties of the resulting polyurethanes. 

The structure - property relationships in polyurethanes (PU) have been excellently presented in the general monographs on PU [1-11]. As a consequence, this chapter will not be very long and it will present only the specific general effects of the oligo-polyol s structure on the resulting polyurethane properties. 

The MW of oligo-polyols, is usually in the range of 400 to 6500 daltons, and it has an important effect on the polyurethane properties. Thus, if the polyol has a low MW, a hard polyurethane will result and if the polyol has a high MW, it creates elastic, flexible polyurethanes. Intermediate MW lead to semirigid or semiflexible structures [2]. 

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