| Polyurethane resin has excellent performance of low temperature resistance,adhesive strength and flexibility, is widely used as a fire retardant coating binders. Inthis paper, poly (ethylene carbonate) propyl diol (PPC) as the polyol component forthe synthesis of the polyurethane resin, then the polyurethane modified with hydroxysilicone oil, and with the the hydroxy silicone oil-modified polyurethane resin as themain film-forming material, by adding the intumescent t flame retardant system toprepare a poly(propylene carbonate) polyurethane fireproof coating with fireperformance and excellent in water resistance. Since the PPC is the use of carbondioxide as a row material synthesized, the polymer is biodegradable, this study hasgreat significance in the CO2recycling and protecting the ecological environment.And PPC own high carbon content, is conducive to the establishment of the carbonskeleton during the combustion. thereby delaying combustion, protect the substrate.This study is divided into two parts, the first part is to prepare theone-component poly (propylene carbonate) polyurethane fire retardant paint. Use ofpoly (propylene carbonate) diol (PPC) and toluene diisocyanate (TDI) synthesisprepolymer,1,4-butanediol (BDO) as chain extender, synthetic polyurethane binders,and then added intumescent flame retardant system composed by the poly-ammoniumpolyphosphate (APP), melamine (MEL) and pentaerythritol (PER), prepared fireretardant coating. The synthesis of polyurethane that the R-value (The ration of-NCOgroup and-OH group), the prepolymerization conditions and the chain extenderconditions were optimized, while for the content of the flame retardant system and aratio of each flame retardant agent were discussed. The results show that when theR-value of1.4, the prepolymer conditions of70℃for3h and the chain extenderconditions of70℃for2h. the fire retardant coating has a good fire performance andwater resistance. Use the hydroxyl silicone oil modified polyurethane, the study foundthat with the increase in the content of hydroxyl silicone oil, fire-resistant of the fireretardant paint were increases at the first and then decreases; When the hydroxysilicone oil content of3%of the polyurethane effective content, there will haye a bestfire performance of fire-resistant coating. Three flame retardants in flame retardant system have a great impact on the expansion, foam of fire retardant paint coating witha different proportion, and ultimately the formation of carbonaceous layer will bedifferently. When APP:MEL:PER ration of30:25:15, the combustion of fire-resistantcoating to form carbonaceous layer is high and continuous, fire effect is the better;With the increase in the amount of flame retardant system, fire-resistant of the fireretardant paint have a significantly improved at the first and then a slight decrease;when the amount of flame retardant system for polyurethane80%of the solid mass,fire-resistant coating refractory time of725s, the fire prevention works better.The second part is prepared bicomponent polyethylene propylene carbonate typepolyurethane fire retardant coating. PPC, TDI, BDO, and hydroxyl silicone oil wasused to synthesize bicomponent polyurethane component A (-NCO component), thecomponent A and component B (commercially available polyhydroxy component)mixed in proportion, and then add the flame retardant system to prepare thetwo-component poly(propylene carbonate) polyurethane fire retardant coating.Discussion A component optimum synthesis conditions for R-value of2.3, theprepolymerization conditions were70℃for1h, the chain extender conditions of70℃for1.5h, the hydroxy silicone oil used in an amount of5%of the polyurethaneeffective content. the proportion of A component in the fire retardant coating havesome influence in fire performance of fire retardant coating and water resistance. Withthe increase of A component in the proportion of two-component fire retardant coating,the fire-resistant of fire retardant coating were increases at the first and then decreases;as well as the water resistance. When the components A and B components weremixed in a2:1mass ratio, add intumescent flame retardant system to prepared fireretardant paints that refractory time of904s, and the water resistance have a goodperformance.Finally, the performance and structure of the two fire retardant coating wereanalyzed by some test instruments like the physical and chemical properties ofcomparison, a digital photo image analysis, thermogravimetric analysis (TG) Thephysical and chemical properties of comparison shows that the drying time, hardnessand water resistance of the two fire retardant coating are good, and thetwo-component fire retardant coating performance is better than the one-componentfire retardant coating; digital photo image analysis shows that the combustion of thetwo-component fire retardant coating formed more higher and continuouscarbonaceous layer than the one-component fire retardant coating; TG analysis showed that the residual carbon content of the two fire retardant coating andcarbonation level increased, the formation of carbonaceous layer has a certainthickness, and good thermal insulation, oxygen barrier and smoke suppressionperformance. |
PDF Full Text Request