Poly worm

Poly(methyl methacrylate). PMMA offers distinct advantages over BPA-PC with respect to significandy lower birefringence, higher modulus, and lower costs, but has not been successhil as a material for audio CDs and CD-ROM as well as a substrate material for WORM and EOD disks because of its high water absorption (which makes it prone to warp) and its unsuitabiUty for metallising, and less so because of its low resistance to... 

Several of the current synthetic semi-fluid lubricants for worm gears are based on a poly-alkaline glycol - which possesses slipperiness . Oxidation and rust-inhibitors are... 

Fig. 67 Schematic of phase behaviour for blend of novolac epoxy resin with nearly symmetric poly(methyl acrylate-co-glycidylmelhacrylate)-0-polyisoprene. Ordered L can be swollen with up to about 30% of resin before macroscopic phase separation occurs, producing heterogeneous morphologies containing various amounts of L, C, worm-like micelles and pristine epoxy. At lower concentrations, disordered worm-like micelles transform into vesicles in dilute limit. According to [201]. Copyright 2003 Wiley...

Neanthes arenaceodentata is the most sensitive marine organism yet tested. In worms exposed to sublethal concentrations of CC6, feeding was disrupted after 14 days at 79 pg/L (USEPA 1980), reproduction ceased after 440 days (three generations) at 100 pg/L (Oshida et al. 1981), brood size was reduced after 309 to 440 days at 12.5 to 16.0 pg/L (Oshida et al. 1981 Oshida and Word 1982), and abnormalities in larval development increased after 5 months at 25 pg/L (Reish 1977). On the other hand, exposure for 293 days (two generations) in 50,400 pg Cr+3/L caused no adverse effects on survival, maturation time required for spawning, or brood size (Oshida et al. 1981). The poly-chaete Capitella capitata was more resistant than Neanthes, a decrease in brood size was noted only after exposure for 5 months to 50 and 100 pg Cr+6/L (USEPA 1980). 

Anderson, S.L., F.L. Harrison, G. Chan, and D.H. Moore II. 1990. Comparison of cellular and whole-animal bioassays for estimation of radiation effects in the polychaete worm Neanthes arenaceodentata (Poly-chaeta). Arch. Environ. Contam. Toxicol. 19 164-174. 

The variation of the domain sizes with crosslink density was recognized by Yeo et al. [28], investigating cross-poly(n-butyl acrylate)-inter-cross-polystyrene. Figure A shows the morphology of 50/50 compositions as a function of network I crosslinking level. The cellular structures are gradually transformed to finer, and more obviously cylindrical or worm-like shapes with increasing crosslink density. 

Fig. 23. Crystal structure of /Worm (modification-/) poly (vinylidene fluoride). Figures in broken lines represent chain rotation to avoid the steric hindrance between F atoms (Hasegawa and others, 1970)...

An alternative view of the polysilane structure is depicted using the worm-like model as proposed for poly(diacetylene)s59, where the linear chain has a large number of small twists without sharp twists playing a special role60-62. In this model, a Gaussian distribution of site energies and/or exchange interactions and the coherence of the excitation is terminated by any of the numerous usual random deviations from perfect symmetry. 

Mitterer, R. M. Comparative amino acid composition of calcified and non-calcified poly-chaete worm tubes. Comp. Biochem. Physiol. 38B, 405-409 (1971). 

The points in Fig. 24 represent the experimental values of A for a ladder poly-dichlorophenylsfloxane and cellulose carbanilate For both polymers the experimental data are in agreement with theoretical Curve 4 corresponding to the value of d/A = 0.5 for a kinetically flexible chain polymer. This qualitatively demonstrates that the hydrodynamic properties of the molecules of these two polymers at low X differ from those of an infinitely thin worm-like model. However, to obtain quantitative agreement between theory and experimental data according to Curve 4 in Fig. 24, A/d should be equal to 2 — a reasonable value for many flexible-chain polymers not realistic for such r d-chain polymers as ladder polysiloxanes or cellulose ethers and esters. 

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