【摘要】 利用超临界二氧化碳(SC CO2)作为单体的溶剂和聚丙烯的溶胀剂,通过自由基接枝聚合合成了聚丙烯与丙烯酸、甲基丙烯酸甲酯以及马来酸酐的接枝产物PP-g-(AA-MMA-MAH).在单体的选择上采取软、硬单体复配的方式来调节链的柔韧性.考察了溶胀条件、接枝条件以及单体配比对接枝反应的影响,研究结果表明,PP和单体以及引发剂在7.74MPa、47℃下溶胀5h后,75℃下反应3h时接枝率为4.31%,接枝效率可达71.83%.产品表征说明单体均匀地接枝到聚丙烯颗粒上;改性后聚丙烯水润湿角降低,亲水性能得到明显改善;接枝单体的引入提高了PP的热稳定性.更多还原

【Abstract】 Polypropylene (PP) was swelled with a solution of monomers in supercritical carbon dioxide (SC CO2), and was grafted with acrylic acid (AA), methyl methacrylate (MMA) and maleic anhydride (MAH) via free radical polymerization leading to PP-g-(AA-MMA-MAH). During monomer selection, combination of soft monomer and hard monomer was used in order to tune flexibility of grafted polymer. The effects of different experimental conditions such as impregnation conditions, reaction conditions and ratio of monomers on grafting reaction were studied. The results indicated that the maximum grafting degree and grafting efficiency of PP with AA, MMA and MAH reached 4.31% and 71.83% respectively under the optimal swelling conditions at 7.74 MPa and 47 ℃ for 5 h, and reaction conditions at 75 ℃ for 3 h. After being grafted, the monomers were uniformly distributed in the PP substrate; the water contact angle of the grafted PP decreased, indicating the improvement of hydrophilicity; thermal stability of the product was improved because of introducing the grafted monomers.更多还原