Auburn International, Inc.

Thomas B Smith

Ronald L Dechene

Ajoy K Roy

Scott A Marino

Ronald J Tache

David R Day

Christian I Tanzer

Robert E Newton

Tadd B Hughes

Gary H Tougas

An on-line nuclear magnetic resonance (NMR) system, and related methods, are useful for predicting one or more properties of interest of a polymer. In one embodiment, a neural network is used to develop a model which correlates process variables in addition to manipulated NMR output to predict a polymer property of interest. In another embodiment, a partial least square regression technique is used to develop a model of enhanced accuracy. Either the neural network technique or the partial least square regression technique may be used in conjunction with a described multi-model or best-model-selection scheme according to the invention. The polymer can be a plastic such as polyethylene, polypropylene, or polystyrene, or a rubber such as ethylene propylene rubber.

Partial least square regression techniques in obtaining measurements of

A real-time, on-line nuclear magnetic resonance (NMR) system, and related method, can predict various properties of interest of a sample of polymer material. A regression or neural network technique is used to develop a model based upon manipulated NMR output and a resin age factor which compensates for time dependent aging phenomena and enhance predictive accuracy of the model. In a preferred embodiment, the resin age factor is a function of elapsed cycle time prior to sample measurement, sample temperature at time of measurement, and/or sample form. The polymer can be a plastic such as polyethylene, polypropylene, or polystyrene, or a rubber such as ethylene propylene rubber.

Using resin age factor to obtain measurements of improved accuracy of

Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay (FID) curves (C), from which fast Gaussian, slower modified Gaussian or preferably slower Gaussian, and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the FID curve components to the physical quantities of the target nuclei.

NMR analysis of polypropylene in real time

Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which Abragam, Gaussian, and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the curve components to the target nuclei.

Magnetic resonance analysis in real time, industrial usage mode

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.

Obtaining measurements of improved accuracy of one or more polymer

A pulsed NMR analysis system and process comprising an on-line system to extract a sample and establish digitized free induction decay curves (C), from which curve components functions are determined using regression techniques to correlate the curve components to the target nuclei, crystalline or amorphous, and to other material characteristics, such as flow rates in plastic (MI and FRR for polyethylene and MF for polypropylene). The invention makes use of Principal Component Analysis (PCA) for deriving an orthogonal set of explanatory parameters and therefrom a set of vectors wherein collinearity is eliminated by Eigenvalue analysis.

Measurement of material composition and properties

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.

NMR system for measuring polymer properties

Apparatus and process for measuring mass flow of a slurry mixture of two components of materials, such as a flow of catalyst solid particles (the first component) or droplets in a fluid carrier (the second component). The slurry mixture is added to a process stream (10) or batch reactor. The flow velocity and the volume fraction of one component are measured and combined with the known specific gravity, of the component being measured, and the physical dimensions of the pipe, in which the slurry mixture is flowing, to determine the mass flow of the component. The flow velocity is measured by correlating signals at two separated locations along the flow path, and the volume fraction is measured by combining the known dielectric constants of each of the materials in the mixture and the measured capacitance of the mixture. The capacitance is measured from electrodes which may be isolated from the flowing materials in some applications, but not isolated from the flowing materials in other applications. The temperature (9) and pressure (11) are compensated in the final calculation, and the mass flow result is used to control, via feedback, the amount of such materials delivered. Also, a subtraction technique to remove interfering power line noise is implemented to improve sensitivity.

On-line mass flow measurement in flowing two component systems

A pulsed NMR analysis system and process comprising an air curtain (137), 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 nonlinear regression techniques to correlate the curve components to the target nuclei and to flow rates in plastic including MI and FRR for polyethylene and MF for polypropylene.

Apparatus to obtain flow rates (melt index) in plastics via fixed

A pulsed NMR analysis system and process comprising 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 non-linear regression techniques to correlate the curve components to the target nuclei.

Real time magnetic resonance analysis with non-linear regression means

Pulsed NMR system for industrial measurements comprising sample throughout system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which Abragam, Gaussianand exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the curve components to the target nuclei.

Magnetic resonance analysis in real time industrial usage mode

Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay (FID) curves (C), from which fast Gaussian, slower modified Gaussian and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the FID curve components to the physical quantities of the target nuclei.

Particle analysis apparatus (10) in combination with a triboelectric probe (P) and including means (18, 20, 22, 24, 26) to analyze individual particle collisions with the probe as a useful measure of flow conditions--of a fluid with suspended solid particles--in the region of the probe.

Flow measurement by collision characterization

Pulsed NMR system for industrial purposes comprising sample throughput system (P, LI, V1, V2) magnetic field adjustment (120, 124) and thermal adjustment (134-138 and 142-146). The resonance is established by a coil (100), excited by a transceiver (104) and interacting with the sample and the magnetic field at resonance to establish received and digitized free induction decay curve forms (C) which are automatically analyzed into Gaussian and exponential components--providing simplified high speed computation means with repetitive test sequence and thermal controls that systematically minimize errors to assure reliable determination of target nuclei quantities in successive samples from an industrial process and utilizing Hahn spin echo based equipment to automatically adjust the analysis of one or more of the analyzed components.

Magnestic resonance system for industrial purposes comprising sample throughput system (P, LI, V1, V2) magnetic field adjustment (120, 124) and thermal adjustment (134-138 and 142-146). The resonance is established by a coil (100), excited by a transceiver (104) and interacting with the sample and the magnetic field at resonance to establish received and digitized free induction decay curve forms (C) which are synthesized into bound (Gaussian) and unbound (exponential) components--pairing simplified high speed computation means with repetitive test sequence and thermal controls that systematically minimize errors to assure reliable determination of target nuclei quantities in successive samples from an industrial process.

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Atkinson, NH, United States of America

Thomas B Smith