Polyurethane sandwich panels in the polyurethane is what material, what are the benefits of industrial building materials should choose polyurethane?
Foam benzene board capacity of not less than 18kg, other indicators in line with national regulations
Extrusion board is different from the foam board, bulk density can not be arbitrarily changed, the technical units to do relatively light But not less than 30kg / cubic meter is generally 35kg / m3 or so manufacturers and manufacturers different
It should be, for example, naphthalene anthracene, and several rings are capable of forming a closed conjugate system. Generally speaking, more than four benzene rings are fused (for example, 1.2-benzo, 3-methyl Anthracene, etc.) are mostly carcinogenic substances, which are mostly anthracene derivatives, the relationship between the mechanism of carcinogenesis and structure is not yet fully understood ...
