SGER: A New Approach to Composition Separation in Crystalizable Copolymers

小行星9812261 本次SGER奖中提出的研究代表了一种加速共聚物结晶溶解过程的新方法。 速度是必要的，以增加类似成分的材料可以分离的速率。 升温洗脱分级（TREF）目前用于基于相对结晶度分离可结晶共聚物，并获得共聚物内的组成分布。 TREF的结果是使用所谓的“单活性中心催化剂”开发最新一类聚烯烃的关键。 然而，与其他成分分离技术一样，TREF是缓慢的。 拟议的研究使用TREF作为一个起点，以确定这些基本参数，控制分离，在这样的系统。 所提出的研究的结果将是将可结晶共聚物中的TREF分析时间从数天减少到1小时。 提高分离速度的一种方法是将TREF转换为真正的 当物质沿柱沿着移动时，组分之间的分离增加的色谱技术。 这是以前从未尝试过的，是对常规的极大背离。 将使用TREF的区域精制型改进将色谱特征引入分离工艺。 如提案中所述，最终形式既不是区域精炼也不是TREF，但可能将分析时间减少50倍。 补充方法可能有助于分离，也存在色谱方法的其他途径。 这些将根据需要进行评价。 %如果成功的话，通过“区TREF”的可结晶聚合物的组成分布可以成为通过GPC的分子量分布或通过DSC的熔融结晶度评估的标准。 考虑到快速成分分析可能对塑料行业产生的潜在影响，特别是聚烯烃行业，通过SGER赠款对这种拟议方法进行早期评估是可取的。 ***

9812261 Harrison The proposed research in this SGER Award represents a new approach to speeding up crystallization-dissolution processes in copolymers. Speed is necessary to increase the rate at which similar-composition materials can be separated. Temperature- Rising Elution Fractionation (TREF) is currently used to separate crystallizable copolymers based on relative crystallizabilities, and to obtain a distribution of compositions within the copolymer. Results from TREF were key in developing the latest class of polyolefins using so called `single-site catalysts'. However, like other composition separation techniques, TREF is slow. The proposed research uses TREF as a starting point to identify those fundamental parameters that control separation in such systems. An outcome of the proposed study would be to reduce TREF analysis times in crystallizable copolymers from days, to an hour. One approach to increasing separation speed is to turn TREF into a true chromatographic technique where separation between components increases as material moves along a column. This undertaking has never before been attempted and represents a dramatic departure from the norm. A zone refining type modification of TREF will be used to introduce chromatographic character into the separation process. The final form, as described in the proposal, is neither zone refining nor TREF but could potentially reduce analysis time by a factor of 50. Supplementary methods may aid in separation and other routes to the chromatographic approach also exist. These will be evaluated as required. %%% If successful, composition distribution in crystallizable polymers by `zone TREF' can become as standard as molecular weight distribution by GPC, or melting-crystallinity evaluation by DSC. Given the potential impact which rapid composition analysis could have on the plastics industry in general, and the polyolefin segment in particular, early evaluation of this proposed methodology through a SGER grant is desirable. ***