Research On Preparation And Properties Of Flame Retardant Polyurethane Rigid Foam Based On Soybean Oil

Polyurethane rigid foam(RPUF)has a wide range of applications.However,the porous structure of polyurethane makes it extremely easy to burn and release toxic gases.In addition,the raw material of traditional polyurethane foam polyols are derived from non-renewable fossil resources.Therefore,it is necessary to improve the flame retardant properties and develop renewable resources as raw materials for polyurethane foam.Soybean oil is a low-cost,high-yield renewable resource,coupled with the unsaturated double bond in the molecular chain,which lays the foundation for its modification.In this paper,the soybean oil-based polyol has reacted with isocyanate to prepare the soybean oil-based polyurethane rigid foam.The flame retardant is added to improve the flame retardant properties of the foam.The effect of different content of flame retardant on the properties of RPUF has been explored.The main research contents are as follows:(1)Soybean oil-based polyol(HSBP)is obtained from water ring-opening epoxy soybean oil(ESO)and then react with DOPO to prepare the phosphorus-containing soybean oil-based polyol(DOPO-HSBP).Finally,HSBP and DOPO-HSBP are mixed in different proportions,then react with pMDI with addition of catalysts,foam stabilizers and foaming agent to obtain phosphorus-containing polyurethane rigid foam.We take the characterization for the structures of HSBP and DOPO-HSBP by FT-IR and~1H NMR.At the same time,the effects of different content of DOPO-HSBP on density,cell structure,mechanical properties,thermal stability and flame retardant properties of phosphorus-containing polyurethane rigid foam are discussed.(2)Nitrogen-containing polyol(T-D)is obtained from ring-opening ethylene glycol diglycidyl ether(TMA)ring-opened by diethanolamine(DEA).HSBP,T-D and DOPO-HSBP are mixed in different proportions,and catalysts,foam stabilizers and foaming agent are added.Then the mixture reacts with pMDI to prepare the polyurethane rigid foam containing phosphorus and nitrogen.We take the characterization for the structures of T-D by FT-IR and~1H NMR.At the same time,the effects of different contents of DOPO-HSBP on the density,cell structure,mechanical properties,thermal stability and flame retardancy of phosphorus and nitrogen-containing polyurethane rigid foam are discussed when the content of T-D is certain.(3)HSBP,expanded graphite(EG)and DOPO-HABP are mixed in different proportions,and react with pMDI with the addition of catalysts and foam stabilizers to prepare the phosphorus and EG-containing polyurethane rigid foam.In the case of a certain EG content,the effects of different content of DOPO-HSBP on polyurethane rigid foam density,cell structure,mechanical properties,thermal stability and flame retardancy are discussed.