Poly Potential Energy

The other three polymers have additional rotation angles in the side chains, x and/or x. For poly(3-methyl-1-butene), the minimum was found in the three-dimensional plot. For poly(U-methyl-l-pentene) and poly(methyl methacrylate), the stable conformation of the side chain was first calculated with the fixed main chain conformation corresponding to the (7/2) and (5/1) helices, respectively. The potential energy was calculated against the main chain rotation angles, x and t2, by fixing x and x of the side chain at the values thus obtained. ... 

Figure 1. Potential energy map of isotactic poly acetaldehyde. The energy values are given in units of kilocalories per mole of monomer unit (23).

The above potential energy approach of building double helical polynucleotides is illustrated below for some hypothetical B-family poly(dA) poly(dT) chains. For simplicity, the helices are generated as a function of the phosphodiester angles < and u> only. 

Venkatachalam and Ramachandran (1967) have evaluated the various nonbonded potential functions described in Section VB, by using them to calculate nonbonded potential energy contours for the dipeptide glycyl-L-alanine and for helical poly-L-alanine. The functions considered were those of Brant and Flory (1965c), De Santis et al. (1965), Scott and... 

Gerasimov et al. have reported that poly-p-PDA Et is obtained quantitatively at 170 - 4.2 K and that the activation energy is 1600 300 eal/mol at 170 - 100 K and close to zero (<20 cal/mol) at 90 — 4.2 K, respectively. From the outstanding reactivity of p-PDA Et at an extremely low temperature, the barrier to the reaction in the monomer crystals has been attributed to the force of the crystal lattice and classified into the region of negative values of the potential energy. In addition the observed induction period at 4.2 K has been attributed to the growth period of crystal defects (see Sect. IV.a.) In the case of DSP, quantitative conversion of monomer to polymer crystals has been achieved by photoirradiation at — 60°C26). 

Raman spectral-band frequencies for poly (thietane) as a crystallized melt annealed at 62° satisfy the rules for a longitudinal acoustic-mode frequency for deducing thickness. The morphology and physical properties of isoprene thietane block copolymers have been studied. Potential energies have been calculated for helical- and glide-type conformations of poly (thietane), and the conformations of the homopolymer have been calculated. ... 

PAH PES PTPE PVD PVDP polycyclic aromatic hydrocarbon potential energy surface poly(tetrafluoroethylene) physical vapor deposition poly(vinylidene difluoride)... 

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