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Isocyanate modified liquid was prepared by isocyanate and diluted asphalt. Then, isocyanate modified asphalt cold patch asphalt mixture was prepared by combining isocyanate modified liquid with aggregates. Crosslinking reaction was used to improve the performance of cold patch asphalt mixture. The experimental results show that the modified liquid exhibits good short-term storage stability. By adjusting the dosage of PM-200 and PPU-1102 isocyanate, the viscosity and the reactivity of the system can be effectively regulated, from which the mechanical properties and water damage resistance of the cold patch asphalt mixture can be well adjusted. When the proportion of diluted asphalt, PM-200 and PPU-1102 in the modified liquid are 50%, 10% and 40%, respectively, the Marshall stability and the residual stability of the cold patch asphalt mixture with 6% liquid content reaches 24.8kN and 86.1%, respectively, which are close to those of the hot asphalt mixture. Field experiments show that compared with traditional material, the isocyanate modified cold patch asphalt mixture exhibits higher durability. [ABSTRACT FROM AUTHOR]

In order to cope with the problems of low activity and insufficient performance of organic polymer mortar under low temperature in winter, a preparation method of unsaturated polyester mortar was studied. Through the design of the initiator system, the effective controllable curing under low temperature environment was realized. The effects of the ratio and dosage of initiator, promoter and filler systems on the operable time, operability, flow resistance and mechanical properties after curing of mortar were studied, while the influencing mechanism of each component on different properties was analyzed. The influence of reducing agent and other components on shrinkage rate and mechanical properties of mortar were explored and the shrinkage of mortar was effectively controlled by foaming expansion technology. Finally, a low temperature organic mortar with ideal comprehensive performance was prepared, which exhibited a good prospect of application. When the quartz sand is 1.5 times the amount of unsaturated polyester, the amount of silica black and initiation system is 12% and 3% of UR, respectively, and the system is combined with NaHCO3 and lactic acid of equal equivalent, which account for 2% of UR mass, the system has no shrinkage after curing, the compressive strength at -5 °C is higher than 80 MPa, and it has excellent flow resistance and suitable construction window. It has better comprehensive performance. [ABSTRACT FROM AUTHOR]