Probing the origins and control of shrinkage stress in dental resin composites. II. Novel method of simultaneous measurement of polymerization shrinkage stress and conversion
Probing the origins and control of shrinkage stress in dental resin composites. II. Novel method of simultaneous measurement of polymerization shrinkage stress and conversion
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DOI：
10.1002/jbm.b.30088
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发表时间：
2004-10-15
影响因子：
3.4
通讯作者：
Bowman, CN
中科院分区：
文献类型：
--
作者：
Lu, H;Stansbury, JW;Bowman, CN
本研究通过一种新颖的实验技术探讨了聚合收缩应力发展与聚合进程之间的相互关系。该技术能够使用非侵入性近红外光纤系统以及基于悬臂梁的张力计实时、同步测量双键转换和收缩应力。填充和未填充的 bis-GMA/TEG-DMA（70:30 质量比）体系的结果表明，收缩应力的积累集中在聚合的后期阶段，其急剧增加与其极限值的渐近转换有关。收缩应力随玻璃化状态转变的单调增加归因于玻璃化阶段样品弹性模量的急剧增加以及当样品因放热聚合和光吸收引起的温度升高而冷却时产生一定量的冷却应力。聚合动力学评估和收缩应力测量均具有出色的重现性。 (C) 2004 年 Wiley 期刊公司。
This study probes the interrelationships between polymerization shrinkage stress development and the polymerization progress with a novel experimental technique. This technique is capable of real time, simultaneous measurement of double-bond conversion and shrinkage stress with the use of a noninvasive near-infrared fiber-optic system, along with a cantilever beam-based tensometer. The results from both filled and unfilled bis-GMA/TEG-DMA (70:30 mass ratio) systems showed that the shrinkage stress buildup was concentrated in the latter stages of polymerization, with its dramatic increase linked to the asymptotic approach of conversion to its limiting value. The monotonic increase of shrinkage stress with conversion in the vitrified state is attributed to the dramatic increase of the sample's elastic modulus during the vitrification stage and a certain amount of cooling stress as the sample cools down from the temperature rise caused by the exothermic polymerization and light absorption. Excellent reproducibility of both the polymerization kinetics assessment and the shrinkage stress measurement has been achieved. (C) 2004 Wiley Periodicals, Inc.