Polyfunctional Monomer And Pcl Radiation Crosslinking

A novel and effective solid-acid-catalyst SO₄^2-/TiO₂/La³⁺ was prepared by baking. And two kinds of polyfunctional monomers (PFM) were high efficiently synthesized by using SO₄^2-/TiO₂/La³⁺ as catalyst. The main factors influenced activity of catalyst and esterifacation rate, such as the preparing condition, the ratio of acid vs alcohol, the amount of catalyst and polymerization retarder, the esterification temperature and time, were studied carefully. The results showed that when the ratio of methacrylic acid vs butanediol was 2.8:1, the amount of catalyst and retarder hydroquinone were 1.2%> 1.0% respectively, the esterification rate of butanediol dimethylacrylate was high as 92%, and when the ratio of crylic acid vs pentaerythritol was 3.5:1, the amount of catalyst and retarder were 2%, 1.5% each, the esterification rate of pentaerythritol triacrylate was 78.5%.We used the PFMs prepared above to enhance radiation crosslinking of PCL. The influences of the usages of PFMs, the numbers of functional group of the PFMs, and the radiation dosage on the radiation crosslinking law and mechanical properties of PCL, respectively, were investigated. It was founded that the efficiency of radiation crosslinking of PCL be greatly improved by the presentation of PFMs. The more the usage and the functional group number of the PFM, the more gel content and the more distinctive the radiation crosslinking effects were. This also indicated that the PFMs directly participated in the crosslinking reaction.The effects of Calcium Phosphate powder (CPP) on the mechnical properties of PCL was also studied here. It was concluded that, the mechanical properties of PCL was greatly enhanced with the addition of CPP, the more the usage of the CPP, the greater the strength of PCL was. Combining the enhancing radiation effect of PFM and the strengthen effect of CPP, the mechanical properties of the blend PCL-PFM-CPP was greatly improved.