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With combinatorial materials research (CMR), a new research approach toward the development and optimization of materials has been established at BASF. While adopting the basic ideas of combinatorial chemistry, CMR faces a whole bunch of challenges throughout the entire combinatorial process loop. New concepts for sample preparation on a smaller scale, i.e. synthesis and formulation, for parallel or fast sequential screening and characterization, and for appropriate management of yet unknown amounts of data have been developed. The integration of as many as possible workflow steps and the interplay of experts from various relevant fields, such as chemistry, engineering, robotics, informatics, and physics, are necessary. First results in the fields of polymer synthesis and coatings formulation give an impression of the innovative power and efficiency of this new kind of research. magnified image

SUMMARY: Free-radical copolymerizations of ethene (E)-methacrylic acid (MAA) and of E-acrylic acid (AA) have been carried out in a continuously operated device at 2 000 bar and at temperatures between 240 and 280 8 C. Even at low degrees of overall monomer conversion, below 1%, and at small (M)AA contents of the copolymerizing mixtures, below 0.5 mol-%, the resulting copolymer is not soluble in the reaction mixture at contents of acid units well above 6 mol-%. At such low (M)AA contents, the classical procedure of deriving both reactivity ratios, r E and r (M)AA , from fitting monomer and copolymer compositions to the differential copolymerization equation is not applicable. r E may be estimated by this procedure, but the composition range is too small to derive r (M)AA . Data for r (M)AA may, however, be deduced from relative amounts of (M)AA-centered triad sequences that are available from quantitative 13 C NMR spectroscopy of the copolymer. Because of assignment problems for the E-(M)AA copolymers, the 13 C NMR studies have been carried out on product samples after complete methyl-esterification to yield E-methyl(meth)acrylate copolymeric material. The resulting r MAA data are slightly above the r AA values. The numbers, e. g., for 240

Poly(ethylene terephthalate) (PET) was studied by the technique called dynamic infrared spectroscopy with the use of digital signal processing. The dynamic infrared signals of PET were correlated with the reorientation movement of functional groups and the deformation of internal coordinates, which depend upon the morphology of the sample. With the use of this novel approach, it is demonstrated that the internal coordinate change of the trans C–O bond plays an important role in the macroscopic deformation of oriented PET; the reorientation movement is differentiated in the case of unoriented PET, where the phenyl ring contributes more in such a process.

SUMMARY Uniaxially drawn syndiotactic polystyrene (sPS) in various modifications has been analyzed by static difference polarization spectra and DIRLD (dynamic infrared linear dichroism) spectra during mechanical stretching. Both, derivative bipolar bands and monopolar bands, are observed as a hint to submolecular changes induced by the applied external strain. The lineshape features in the dynamic in-phase spectra are described on the basis of frequency shifts and absorption amplitude variations during the stretching cycle. The conformationally sensitive vibrational modes are most sensitive to the external perturbation. The different responses of the conformationally insensitive vibrational modes to the external perturbation are discussed.