Obtaining measurements of improved accuracy of one or more polymer
properties with an on-line NMR system
    1.
    发明授权
    Obtaining measurements of improved accuracy of one or more polymer properties with an on-line NMR system 失效
    使用在线NMR系统获得改进的一种或多种聚合物性质的精度的测量

    公开(公告)号:US5519319A

    公开(公告)日:1996-05-21

    申请号:US491632

    申请日:1995-06-19

    摘要: A nuclear magnetic resonance (NMR) system, and related method, develops two or more regression equations or models for a particular polymer property of interest (e.g., melt index or MI) during a calibration procedure using known samples of a material. The polymer material can be, for example, a plastic (e.g., polyethylene, polypropylene, or polystyrene) or a rubber (e.g., ethylene propylene rubber). Regression models for one or more discrete (i.e., two-valued) variables also are developed during calibration, and these models allow a prediction to be made about which of the two or more property (e.g., MI) models should be used for any particular sample of unknown material. The prediction obtained from the discrete variable model indicates which of the two or more models will produce the most accurate estimation of the property of interest for the unknown sample. The best model is thus selected, and then it is used to estimate the property of interest.

    摘要翻译: 核磁共振(NMR)系统和相关方法在使用已知材料样品的校准过程期间针对特定的感兴趣的聚合物性质(例如熔体指数或MI)开发两个或多个回归方程或模型。 聚合物材料可以是例如塑料(例如聚乙烯,聚丙烯或聚苯乙烯)或橡胶(例如乙丙橡胶)。 在校准期间,还开发了一个或多个离散(即二值)变量的回归模型,这些模型允许对两个或多个属性(例如,MI)模型中的哪一个应用于任何特定的模型进行预测 未知材料样品。 从离散变量模型获得的预测表明两个或更多个模型中的哪一个将产生未知样本的关注属性的最准确估计。 因此选择最佳模型,然后用于估计感兴趣的属性。

    NMR system for measuring polymer properties
    2.
    发明授权
    NMR system for measuring polymer properties 失效
    用于测量聚合物性质的NMR系统

    公开(公告)号:US5408181A

    公开(公告)日:1995-04-18

    申请号:US113833

    申请日:1993-08-30

    摘要: A pulsed nmr analysis system for polymers materials extracted from industrial processes at a mobility enhancing temperature (at or above glass transition temperature for amorphous polymers, at the crystalline transition temperature for crystalline and semi-crystalline polymers). The sample is measured via nmr techniques and results correlated to viscosity and melt index or melt flow (which are related to average molecular weights). The nmr system (in or out of resonance) includes: sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which components functions are determined using linear or non-linear regression techniques to correlate the curve components to the target nuclei and to flow rates in plastics. Substantial improvement of correlation of nmr derived constants and equations of a free induction decay curve with the foregoing polymer properties is obtained via (1) conducting the nmr process at a mobility enhancing temperature (normally elevated compared to the industrial process temperature of the industrial process) and (2) holding temperature substantially constant at such elevated temperature.

    摘要翻译: 用于在工业过程中以迁移率增强温度(对于无定形聚合物的玻璃化转变温度以上,在结晶和半结晶聚合物的结晶转变温度下)提取的聚合物材料的脉冲nmr分析系统。 样品通过nmr技术测量,结果与粘度和熔体指数或熔体流动相关(与平均分子量相关)。 nmr系统(进出谐振)包括:采样吞吐系统(P,LI,V1,V2)和用户系统控制(104)建立数字化的自由感应衰减曲线(C),从中可以使用线性 或非线性回归技术来将曲线分量与目标核相关联,并使塑料中的流速相关。 通过(1)以迁移率提高温度(与工业过程的工业过程温度相比通常升高)进行nmr工艺,获得具有上述聚合物性质的自由诱导衰变曲线的nmr导出常数和方程的相关性的显着改善, 和(2)在这种升高的温度下保持温度基本恒定。