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1. Hydroxyl value Generally, the polyol compound has high functionality and high hydroxyl value, so the foam produced will have high hardness, good mechanical and physical properties

The rising global energy demand requires people to invest heavily in the construction of environmentally-friendly supply infrastructure. Since the birth of polyurethane synthetic materials, it has been gradually used in the field of pipe ....

The history of the development of pipeline insulation materials in my country is: the pipeline insulation materials used in insulation projects in the 1950s are mainly diatomaceous earth products and asbestos carbon-magnesium boards or....

"According to estimates, if all the doors and windows of existing buildings and new buildings that need to be renovated in China are replaced with the European standard polyurethane energy-saving door and window system.....