期刊
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
卷 42, 期 1, 页码 112-129出版社
WILEY
DOI: 10.1002/pola.10964
关键词
methacrylate; solution copolymerization; reactivity ratios; terminal unit model; penultimate unit model; nonlinear least square (NLLS); van Herk method
Copolymers of isobutyl methacrylate (i-BMA) and lauryl methacrylate (LMA) were prepared by free-radical solution copolymerizations at 70degreesC with azobisisobutyronitrile (AIBN) as an initiator. The synthesis of these copolymers was investigated over a wide composition range both at low and high conversion levels. Copolymer compositions were determined from the %C, %H, and %O contents of copolymer by elemental analysis. Monomer reactivity ratios were estimated by analyzing composition data with nonlinear least-squares (NLLS) models based on Marquardt optimization and van Herk methods. The point estimates, 95% individual confidence intervals and 95% joint confidence intervals are obtained from differential and integral approaches. Even though no explicit integral form for penultimate unit model (PUM) is available, a numerical approach is developed for integral estimation of reactivity ratios from PUM. A simulator program was developed which upon coupling of experimental data, NLLS analysis, and D-optimal criteria calculates the best optimized values of monomer reactivity ratios and monomer feed compositions in a sequential and iterative order for terminal and penultimate unit models. Moreover, the simulator has the capibilities to calculate all features of van Herk method, maximum compositional drift in each monomer feed composition, and data reconciliation. (C) 2003 Wiley Periodicals, Inc.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据