A novel hyperbranched poly(acrylic acid) for improved resin-modified glass-ionomer restoratives.
A novel hyperbranched poly(acrylic acid) for improved resin-modified glass-ionomer restoratives.
复制标题
DOI：
10.1016/j.dental.2011.02.005
复制
发表时间：
2011-05
期刊：
影响因子：
--
通讯作者：
Jun Zhao;D. Xie
中科院分区：
文献类型：
--
作者：
Jun Zhao;D. Xie
目的采用原子转移自由基聚合（ATRP）技术合成新型超支化聚丙烯酸，并对其进行表征，将光固化的甲基丙烯酸酯系在聚丙烯酸上，制备树脂改性玻璃离子聚合物胶结剂，并对其力学强度进行评价。材料与方法采用自缩合乙烯基聚合引发剂ATRP合成超支化聚丙烯酸。研究了催化剂和引发剂浓度对产物分子量（MW）和分枝度（DB）的影响。对实验水泥的抗压强度、直径拉伸强度、抗弯强度、断裂韧性、硬度和耐磨性进行了评价，并与Fuji II LC水泥进行了比较。试验前将样品置于37°C蒸馏水中处理24h。结果催化剂和引发剂的浓度对合成聚合物的分子量和分子量均有显著影响。引发剂的浓度对水泥的CS和DTS值也有显著影响。试验水泥的力学性能显著高于富士II LC， CS为53%，压缩模量为50%，DTS为125%，FS为95%，FT为21%，KHN为96%。试验水泥仅为富士ⅱLC磨料的5.4%，磨损深度为6.4%。结论以新合成的超支化聚丙烯酸为原料，制备了一种新型的树脂改性玻璃离子水泥体系。这种新型的实验性骨水泥在临床上是一种有吸引力的牙科修复材料，可能用于高磨损和高应力承载部位的修复。
OBJECTIVEThe objective of this study was to synthesize and characterize novel hyperbranched poly(acrylic acid)s via atom-transfer radical polymerization (ATRP) technique and tether the photo-curable methacrylate onto the poly(acrylic acid), use these polymers to formulate the resin-modified glass-ionomer cements, and evaluate the mechanical strengths of the formed cements.MATERIALS AND METHODSThe hyperbranched poly(acrylic acid)s were synthesized using a self-condensing vinyl polymerization initiator via ATRP. The effects of the concentrations of both catalyst and initiator on molecular weight (MW) and degree of branching (DB) were studied. Compressive, diametral tensile as well as flexural strengths, fracture toughness, hardness and wear-resistance of the experimental cement were evaluated and compared to those of Fuji II LC cement. The specimens were conditioned in distilled water at 37°C for 24h prior to testing.RESULTSThe concentrations of both catalyst and initiator had significant effects on MW and DB of the synthesized polymers. The concentration of the initiator also significantly affected both CS and DTS values of the cement. The experimental cement showed significantly higher mechanical properties, i.e., 53% in CS, 50% in compressive modulus, 125% in DTS, 95% in FS, 21% in FT and 96% in KHN, higher than Fuji II LC. The experimental cement was only 5.4% of abrasive and 6.4% attritional wear depths of Fuji II LC.CONCLUSIONSThis study developed a novel resin-modified glass-ionomer cement system composed of newly synthesized hyperbranched poly(acrylic acid)s. It appears that this novel experimental cement is a clinically attractive dental restorative and may potentially be used for high-wear and high-stress-bearing site restorations.