The Synthesis And Application Of Polycaprolactone

Polycaprolactone is material which low toxicity and biodegradability. PCL has low glass transition temperature, it can be as the raw materials of polyurethane and the plasticizer of polymer materials. Polylactic acid is plastic which come from reproducible material, it is really worth researching that PCL as plasticizer of PLA.The purpose of this paper is to explore a promising process about PCL, which is cleaner and safer, synthesizing PCL of different molecular weights and different functionality. And for the preparation of polyurethane(PU) and the plasticiser of PLA, invesgating its related properties.Utilize the self-made PCL(2 functionalitiesof,3 functionalities, and 4 functionalities) of different molecular weights, and TMP to synthesize PU according to different ingredients in one-step way. And invesgating PU’s properties, results as follow:For the system of PCL(2)-PCL(3)-BD, PCL(2)-TMP-BD, PCL(2)-PCL(4)-BD, mechanical properties(tensile strength, tear strength, elongation at break) testing indicates:PCL(2)-PCL(3)-BD system are more better than PCL(2)-TMP-BD and PCL(2)-PCL(4)-BD system; the more proportion PCL(2) makes up in the system, the more mechanical properties. For the PCL(2)-PCL(4)-BD and PCL(2)-PCL(4)-BD-TMP system, the mechanical testing resoult shows that the other system is better than the former one, especially the tensile strength, the maximum is 6 times as much. The elongation at break increased from 196% to 434%, tear strength increased from 22.49 kN/m to 69.18 kN/m.Resistance to swelling properties of PCL(2)-PCL(4)-BD system are more better than that of PCL(2)-PCL(3)-BD system, and the more proportion PCL(2) makes up in the system, the worse resistance to swelling properties become. In addition, PCL(2)-PCL(4)-BD and PCL(2)-PCL(4)-BD-TMP is not a difference in resistance to swelling degrees.DSC testing indicates:the higher the molecular weight is, the lower glass transition temperature Tg is. The functionality of PCL affect the glass transition temperature unobviously.Synthesis of polyurethane in terms of data, it can be found that:in the other conditions remain unchanged, the higher the molecular weight of PCL(3) or PCL(4) is, the better the mechanical properties are. The larger the crosslinking density is, the better resistance to swelling properties are. The more proportion soft segment makes up in the system, the lower glass transition temperature Tg is.As the plasticizer of PLA, the results showed that plasticizing effect on PLA is better with that the molecular weight of PCL. And that mainly for the tensile strength decreases faster, bending resistance and impact strength increases rapidly.