ON-LINE MEASUREMENT AND CONTROL OF POLYMER PROPERTIES BY RAMAN SPECTROSCOPY

• Main Authors: ANDREWS, TIMOTHY J, CHANG, SHIH Y, LONG, ROBERT L, YAHN, DAVID A, IMPELMAN, RYAN W, MORROW, DAVID
• Format: Patent
• Language: English; French
• Published: 15.04.2004
• Edition: 7
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR PREPARATION OR CHEMICAL WORKING-UP; THEIR RELEVANT APPARATUS; TRANSPORTING

Methods are provided for determining and controlling polymer properties on-line in a polymerization reactor system, such as a fluidized bed reactor. The methods include obtaining a regression model for determining a polymer property, the regression model including principal component loadings and principal component scores, acquiring a Raman spectrum of a polyolefin sample comprising polyolefin, calculating a new principal component score from at least a portion of the Raman spectrum and the principal component loadings, and calculating the polymer property by applying the new principal component sco re to the regression model. The property can be controlled by adjusting at leas t one polymerization parameter based on the calculated polymer property.