Back-bone chain

One of the major drawbacks to many promising copolymers is their unsatisfactory electrochemical stability. Carbonyl groups which feature in many of the back-bone/chain linking groups are likely to cause stability concerns. Likewise, urethane, alcohol, and siloxane functions are sensitive to lithium metal. With this in mind, a recent trend has been to find synthetic routes to amorphous structures with... 

Various types of morphologies and crystalline modifications of s-PS have been reported [44], One of these modifications has an orthorhombic form (space group = P2i2i2i) with a planar zigzag conformation of back-bone chain. This form corresponds to the a-phase found by Kobayashi et al. [35] and to the P-phase named by Guerra et al. [36], The crystal structure of this form was analyzed and the plane of phenyl rings within this form is normal to the chain axis (c-axis) [37-39],... 

The long extensions of the -R groups are three-dimensionally arranged around the polymer back-bone chain, and the floppy chains prevent the formation of a lattice and therefore crystallization. Plasticization with materials ester-benzoates would further separate the molecules and provide more flexible hardened cement. 

Mechanisms for Protection against the Effects of Ozone Attack. The mechanism of antiozonant protection is still not fuUy understood. However, there are several theories, which detail the mechanism of protection by chemical antiozonants inert barrier, competitive reaction, reduced critical stress, and polymer back-bone chain repair. 

For Nylon 6/6, if Ri is chosen as the methyl group attached to the carbon back-bone chain, then R2 must be the amide group and vice versa. 

Comb, monodisperse back-bone and monodis- = perse side chains, random coupling of the side chains along the backbone... 

The VEH results (Fig. 7.35) indicate that, below the dispersed 7t2-band there is a band of less dispersion, corresponding to a ff-band involving the triple bonds in the back bone, and a flat (non-dispersed) band corresponding to the C=0 groups in the 4-BCMU side chains. In the excitation model results (Fig. 7.36), below the 7t2-band there... 

Synthesis of aryl coupled thiophenes and polymerization of these by conventional procedures leads to new copolymers which have different properties compared to the parent polythiophenes. This oligomeric approach towards building novel copolymers has been used to modify the main-chain and also to incorporate fractional amounts of functionalities in the side chains of the polymer back-bone. 

This subblock of the Heat Capacity Data Bank contains empirical as well as theoretical prediction calculations of the heat capacity which are continuously updated. Based on the chemical structure (back-bone, side-chain) as well as on the physical state (glass, crystal, mesophase, liquid, semicrystalline, equilibrium, history), a heat capacity is retrieved. The Prediction Scheme subblock can also be searched for its base, i.e., the precise assumptions which go into the prediction, with documentation to the 1iterature. 

Local energy search, followed by global energy minimization ICM program MC side-chain/back-bone energy > 10 kcal/mol removes rotamer... 

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