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Ordinary people need it Polyurethane foaming machine sometimes，How to distinguish black from white

1, look at the packaging label, packaging marked with "isocyanate" words for black, marked with "composite polyether" words for white

2, look at the color, red barrels for black materials, blue barrels for white materials; The material with dark color is black, and the material with light color is white

Polyurethane foaming machine

The composite polyether is one of the main raw materials of polyurethane rigid foam, also known as white material, and polymerized MDI called black and white material. Suitable for building heat preservation, cold preservation, solar energy, water heater, cold storage, constant temperature storage, beer cans, cold storage and other occasions that need heat preservation and cold preservation. It is composed of polyether monomer, homogenizer, crosslinking agent, catalyst, foaming agent and other components. The appearance is brownish yellow color thick liquid.

Isocyanate is the general term for various esters of isocyanate. If the number of -nco group classification, including monoisocyanate r-n =C=O, diisocyanate O=C= n-r-n =C=O and polyisocyanate.