P eter H. M ühlenbrock, G erhard Fink* M ax-Planck-Institut für Kohlenforschung, Kaiser-W ilhelm-Platz 1, D-45470 Mülheim an der Ruhr Herrn Professor Dr. Dr. h. c. mult. Günther Wilke zum 70. Geburtstag gewidmet Z. N aturforsch. 50b, 423-429 (1995); eingegangen am 7. O k tober 1994 M etallocenes, E thene/a-O lefin Copolym erization, R ate Enhancem ent Effect, Influence of the Tem perature E the...

Temperature responsive poly(N-isopropylacrylamide) (PNIPAM) exhibits a lower critical solution temperature (LCST) of approximately 32 °C in aqueous solution, below which the polymer is water soluble and above which it becomes water insoluble. The LCST of PNIPAM copolymer increases responding to hydrophilic block acrylic acid (AA). The copolymer is pH and temperature responsive. The duel respons...

ExposureofheptanesolutionsofMo(NAr)(CHCMe2Ph)(Me2Pyr)(OAr) (1a;Ar=2,6-diisopropylphenyl), Mo(NAr)(CHCMe3)(Me2Pyr)[OCMe(CF3)2] (1b), and Mo(NAr)(CHCMe2Ph)(Me2Pyr)(OSiPh3) (1c) to one atmosphere of ethylene for 12 h yields the ethylene complexes, Mo(NAr)(CH2CH2)(Me2Pyr)(OAr) (2a), Mo(NAr)(CH2CH2)(Me2Pyr)[OCMe(CF3)2] (2b), and Mo(NAr)(CH2CH2)(Me2Pyr)(OSiPh3) (2c). Addition of 1 equiv of triphenyls...

This study experimentally investigates the effect of processing parameters on mechanical properties of injection molded copolymer. This paper presents an experimental study on the effects of processing parameters including melt temperature, injection pressure and amount preliminary materials on tensile strength of injection molded copolymer PP-WGRT. Polypropylene (PP - supplied by T.P.C of Iran...

The fracture toughnessGc of an interface between the immiscible homopolymers polystyrene (PS) and poly(2-vinylpyridine) (PVP) reinforced with random copolymers, dPSf-r-PVP1-f was measured as a function of the average monomer fraction f and the areal chain density Σ of the copolymer. Long symmetric random copolymers (f ≈ 0.48) are shown to be effective in strengthening the interfaces. The effect...

a copolymer of styrene and methyl styrene was synthesized by nitroxide - mediated “living” free radical polymerization )nmp). n-bromosuccinimide was used as a brominating agent to obtain a copolymer with bromine as its end group. this brominated copolymer was used as macro initiators for atom transfer  radical  polymerization  (atrp).  chemical  modifcation  of  the  clay  and transformation of...

In the title mol-ecule, C(16)H(14)N(2)O(2), the fused cyclo-hexene and pyran rings adopt an envelope and a flattened boat conformation, respectively. In the crystal, N-H⋯N and N-H⋯O hydrogen bonds link the mol-ecules into corrugated sheets parallel to the bc plane.

The title compound, C(21)H(25)ClO, was semi-synthesized from isocostic acid, isolated from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The cyclo-hexene ring has a half-chair conformation, whereas the cyclo-hexane ring displays a chair conformation.

The title compound, C(10)H(11)Cl(5)O, is a chiral mol-ecule with two stereogenic centres. However, it crystallizes as a racemate. One of enanti-omers reveals the relative configuration (2S*,5R*). The cyclo-hexene ring adopts a half-chair conformation.

A simple Pd/SiO2 catalyst which was modified with the ionic liquid [BMPL][DCA] gave an excellent yield of 88% towards cis-2-hexene in the stereoselective hydrogenation of 2-hexyne. The catalyst outperforms, even at full conversion, the commonly used lead-poisoned, toxic Lindlar catalyst and supported colloidal-based Pd as well.