简介:Polyurethane has an excellent flexibility, adhesiveness and high impregnation rate, widely utilized
such as automotive films, insulating materials, and paints. The polyurethane resin is a polymer
which involves the ure简介:Polyurethane has an excellent flexibility, adhesiveness and high impregnation rate, widely utilized
such as automotive films, insulating materials, and paints. The polyurethane resin is a polymer
which involves the urethane bond, obtained by the polymerization reaction between polyisocyanate
and polyol (also called, polyester or polyether).
・・・ ―NCO + HO― ・・ ・・ ―NHCOO― ・・・ (1)
There are several different test methods for measuring hydroxyl groups (-OH) of polyols. In this
application note, the test method using pyridine solution containing phthalic anhydride is applied to
the polyol sample.
The hydroxyl number is expressed as milligrams (mg) of potassium hydroxide as equilibrium
amount of hydroxide groups contained in 1g of sample.详细>