High temperature gel permeation chromatography

聚乙烯和聚丙烯是高吨位塑料，用于制造瓶子、购物袋、包装膜、汽车零件和其他几种应用。这些被称为聚烯烃的塑料非常重要，因为它们的多功能性，低成本和无毒。 聚烯烃是通用的，因为它们的分子可以改变，使产品具有不同的应用性能。通过改变聚乙烯的分子大小分布（正式称为分子量分布- MWD），可以制造具有从蜡（小分子）到非常坚固的材料（如用于制造煤气管的材料）（非常大的分子）的特性的塑料。为了更好地理解这些材料，在分子水平上对其进行表征是至关重要的。这种分子表征可用于提高不同聚烯烃产品的质量。 聚烯烃的MWD是用称为高温凝胶渗透色谱法（HT-GPC）的实验室仪器测量的。该仪器对于了解聚烯烃的生产和应用至关重要。我们目前在这一领域非常活跃，拥有一个旧型号的HT-GPC，不再可靠。该资助提案的目的是为我们的实验室购买一台新的HT-GPC，该仪器具有几项现代功能，将提供有关我们生产的聚烯烃性质的更准确的信息。 聚烯烃分子量分布的知识是研究聚合催化、聚合过程动力学、聚合物加工和结构-性能关系的基础。我们在所有这些领域都有一个非常积极的长期研究计划，由行业和政府资助;通过收购这种新型GPC仪器，该计划将得到极大的增强。

Polyethylene and polypropylene are high-tonnage plastics used to make bottles, grocery bags, wrapping films, automotive parts, and several other applications. These plastics, known as polyolefins, are very important because of their versatility, low cost and non-toxicity.    Polyolefins are versatile because their molecules can be altered to make products with properties for different application. By changing the distribution of molecular sizes of polyethylene (formally know as the molecular weight distribution - MWD), it is possible to make plastics that have properties varying from those of waxes (small molecules) to those of very strong materials such as the ones used to make gas pipes (very large molecules). To better understand these materials, it is fundamental to characterize them at the molecular level. This molecular characterization can then be used to enhance the quality of different polyolefin-made products.    The MWD of polyolefins is measured with laboratory instruments called high-temperature gel permeation chromatography (HT-GPC). This instrument is of the utmost importance for understanding polyolefin production and applications. We are currently very active in this area and own an old model HT-GPC that is not reliable anymore. The objective of this grant proposal is to purchase a new HT-GPC for our laboratories with several modern features that will provide significantly more accurate information on the nature of polyolefins we produce.    The knowledge of the MWD of polyolefins is fundamental for the study of polymerization catalysis, kinetics of polymerization processes, polymer processing and structure-property relationships. We have a very active, long-term research program in all these areas, funded by both industry and government; this program will be greatly enhanced by the acquisition of this new GPC instrument.