The curing process of polyurethanes was investigated with FTIR method. The curves of conversion (α)VS curing reaction time (t) at different temperatures were obtained .The curing reaction of the system was found to be second order reaction. The reaction rate constants and activation energy had been measured. Effect of the use lever of curing agent and temperatures on curing reaction was discussed. The results showed that when the mole ratio of NCO/OH is smaller than 1, the crosslinking reaction take place at high temperature.

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With boron trifluoride methanol complex as raw material, the hydrolysis reaction of boron trifluoride was used to prepare the boric acid. The addition of calcium carbonate is aim to remove the hydrogen fluoride generated in the reaction process, The ultimate objective is making the material being the product of boric acid maximum. Reaction time (T), the ratio of raw materials (molar ratio) and the amount of water were investigated in the influence of the purity and yield of boric acid. The conductivity of mixed solution was determined by conductivity meter, the results determines the end point of the reaction for 20 hours, the optimum solid-liquid ratio is three to one, the amount of water for each mole of boron trifluoride is corresponding 2L distilled water. Product of boric acid yield was 96.26%, the purity was 95.34%.