Preparation And Properties Of Sprayed Low-Surface-Energy Polyurea Materials

Sprayed polyurea elastomer technique is a novel environment-friendly method in the coating field.The successful industrialization and commercialization of sprayed polyurea elastomer is of great importance to improve China's position in the internationally environmental protection field,eco-environmental protection.Besides,it is valuable to achieve the national goals of contamination reduction,energy conservation,and the sustainable development.From the future strategies of building environment-friendly and resource-saving society,the unique advantages of sprayed polyurea elastomers,containing solvent-free ability,pollution-free ability,energy-saving ability,environment-friendly ability and fast curing,make the material quite suitable to be future industrial developing direction of China.Therefore,it is valuable to vigorously publicize and promote the usage of this novel materials.Spayed polyurea elastomer,which combines the advantages of both low surface energy materials and polyurea materials,thus have great potentials in the coating field.It possesses strong compertitive ability in in basic anti-graffiti and stain-resistant materials,wind power blade coatings,and marine antifouling coatings.Through the screening of raw materials and the formulation design,the thesis mainly focused on the preparation of two types of sprayed polyurea materials,the conventional sprayed polyurea elastomer and the low-surface-energy modified sprayed polyurea elastomer.Conventional sprayed polyurea elastomer: On one hand,Component A is composed of diphenylmethane diisocyanate(MDI-50),Polyoxypropylene ether polyols(Tdiol-1000),Propyl carbonate diluent Jeffsol TM PC.With the addition of10% of Jeffsol TM PC and 15% of MDI-50,the raw materials react 3 hours under 80?.On the other hand,Component B is composed of E300(amine chain extender),CAD2000 and CAT5000(amino-terminated Polyoxypropylene Ether),simultaneously with the addition of some silica suxiliaries,anti-oxidants,and UV stabilizers.Meanwhile,the isocyanate index is set as ?=1.1,the Graco H-XP3 main engine is explored to be the spraying device,the FUSION AP spray gun is used in spraying samples,the equipment spraying pressure is set to 15 MPa,the spraying temperature is set to 65 ?.The testing results indicate that the tensile strength of the obtained material is 18.8 MPa,the breaking elongation is 360%,and the peel strength is 96 k N/m.Low-surface-energy modified sprayed polyurea elastomer: On one hand,Component A is composed of MDI-50(diphenylmethane diisocyanate),hydroxyl-terminated polymers and Jeffsol TM PC(propyl carbonate diluent),and the mixing ratio of Tdiol-1000 and Tech-2110 is set to 2: 1.With the addition of 10% of Jeffsol TM PC and 15% of isocyanate,the raw materials react 3 hours under 80?.On the other hand,Component B is composed of E300(amine chain extender),CAD2000 and CAT5000(amino-terminated Polyoxypropylene Ether),simultaneously with the addition of organic fluorine surface-modified additives,silica auxiliaries,anti-oxidants,and UV stabilizers.Meanwhile,the isocyanate index is set as ? =1.1.The testing results indicate that the contact angle is 86.51°,the surface energy is 26.71 m N/m,the tensile strength is 15.1 MPa,the breading elongation is 280%,and the peel strength is 78 k N/m.Besides,the environment-resistant performances of two kinds of polyureas are also observed.The experimental results indicate that both of them possess good medium-resistant,salt error-fog-resistant,weather-resistant abilities,which thus meet the normal industrial protection requirements.Furthermore,the structures of obtained materials are charaterized by NIR spectra.