Isotactic propene/higher α-olefin quenched copolymers at intermediate commoner contents primarily crystallize into a mesomorphic phase.
Several isotactic propene-α-olefin copolymers using 1-octene, ...1-dodecene and 1-tetradecene as comonomers (CiPO, CiPDD and CiPTD, respectively) have been synthesized and their structure and thermal/mechanical/viscoelastic properties have been evaluated. At intermediate comonomer molar content ranged from around 4 to 9, the mesomorphic phase is developed under rather mild quenching conditions and independently of length of the comonomer. Thermal and mechanical parameters diminish as α-olefin content increases and their dependence on composition changes as function of existence of three-dimensional monoclinic crystallites or less ordered entities.
This paper analyzes the application of different bio-inspired and heuristic techniques to the problem of curve fitting in experimental chemistry applications. Two different curve models are ...considered, the well-known Pearson VII function, used before in different curve fitting applications, and a novel hybrid model for transmittance curves, mainly used in the estimation of nitrates concentration in water samples. We describe the performance of an Evolutionary Programming algorithm, a Particle Swarm Optimization technique, a Variable Neighborhood Search algorithm and a Cooperative Coevolution approach in several curve fitting problems, including the processing of real curves such as X-ray diffraction patterns, differential scanning calorimetry curves and transmittance curves of contaminated water samples.
PDF
