High‐Output Polymer Screening: Exploiting Combinatorial Chemistry and Data Mining Tools in Catalyst and Polymer Development

Abstract

High‐output polymer screening (HOPS) combines automated polymerization with online reaction monitoring, rapid polymer characterization and novel fingerprint technology useful in polymer preparation as well as polymer processing and polymer additive development. Originally, HOPS was introduced to develop polymerization catalysts and polyolefin materials more effectively. In comparison to conventional high‐throughput screening, focusing on ultrahigh speed of catalyst screening using arrays of miniaturized reactors, output‐oriented, process‐relevant HOPS is aiming at generating and exploiting high information density (useful information/experiment). Catalyst systems for olefin polymerization are evaluated in automated workstations with multiparallel as well as semi‐ and fully automated, upgraded lab reactors. Automated polymerizations under standardized conditions afford large families of well‐characterized polymers which serve as calibration samples for data analysis. Data analysis, using multivariate calibration, is the key to basic correlations between spectroscopic information and catalyst and polymer properties as well as reaction parameters and processing conditions. IR spectroscopic fingerprints are used to measure chemical copolymer composition, density, molecular weight as well as thermal and even mechanical properties. This fingerprint technology can be applied in online quality control and facilitates transfer from lab results into pilot and production plants. Fingerprint methods are important components of rapid online analysis and can reduce the need for time‐ and money‐consuming polymer testing. Fingerprint technology combines spectroscopic analysis by means of “cheap” spectrometers with multivariate calibration.magnified imageFingerprint technology combines spectroscopic analysis by means of “cheap” spectrometers with multivariate calibration.

Combinatorial and High‐Throughput Materials Science

“…The application of multivariate analysis with NIR has led to the determination of branching, melting points, and molecular weights. [331] 5.10. Gas Sensors Sensors are a growing market in which there are increasing demands on selectivity and sensitivity.…”

“…In a valuable overview, Mülhaupt and co-workers described how the limiting factors can be overcome to allow efficient HT screening of copolymer materials. [331] A typical 5 h per sample HR NMR analysis could be replaced by 40 samples per hour by ATR-FTIR measurements. The authors point out that, for many practical applications, moderate throughput under conditions close to those of real life is advisable.…”

Catalytic 1,3‐Cyclohexadiene Homopolymerization and Regioselective Copolymerization with Ethylene

“…[24] Catalyst activity by means of ethylene consumption was online monitored at 5 and 1.5 bar ethylene pressure, 89 and 97 mol-% CHD, respectively, showing the typical kinetic profile (Figure 4). Starting the copolymerization of ethylene with 1,3-cyclohexadiene, the activity increases continuously to reach the maximum reaction rate at 2 300 g of ethylene consumption per mol of Ti and hour (89 mol-% CHD in feed, Fig.…”

Current Status of Combinatorial and High‐Throughput Methods for Discovering New Materials and Catalysts

“…Recently, various methods for characterizing polymers synthesized by homopolymerization or copolymerization have been suggested [14 -26]. Potyrailo et al [14 -16], Mülhaupt et al [21], and Gabriel et al [23] reported that fluorescence, infrared (IR) and Raman spectroscopies are efficient analytical spectroscopic tools for high-throughput screening. These are correlated with chemical properties of interest, such as molecular weight, degree of branching, and catalyst selectivity.…”