Mechanical Properties and Flame Retardancy of Rigid Polyurethane Foams Containing SiO₂ Nanospheres/Graphene Oxide Hybrid and Dimethyl Methylphosphonate

ABSTRACT

Halogen-free flame-retardant rigid polyurethane foams were prepared using the combination of SiO₂ nanospheres/graphene oxide hybrid and a phosphorus-containing flame retardant, dimethyl methylphosphonate. The flame retardancy, mechanical, and thermal properties of flame-retardant rigid polyurethane foams containing dimethyl methylphosphonate and SiO₂ nanospheres/graphene oxide were investigated. The results demonstrated that the combination of dimethyl methylphosphonate and SiO₂ nanospheres/graphene oxide enhanced flame retardant and mechanical properties of rigid polyurethane foam greatly compared with pure rigid polyurethane foam and dimethyl methylphosphonate-modified foam. Morphological study indicated that the partial substitution of dimethyl methylphosphonate with SiO₂ nanospheres/graphene oxide led to smaller cell sizes and more uniform cell sizes of dimethyl methylphosphonate-modified rigid polyurethane foams.

GRAPHICAL ABSTRACT

KEYWORDS:

• Dimethyl methylphosphonate
• flame retardancy
• mechanical properties
• rigid polyurethane foams
• SiO₂ nanospheres/GO hybrid

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China (No. U1205114)