Chlorinated polyethylene comparison

The incorporation of unmodified and organically modified montmorillonite nanoclays (namely 15A and 30B) in chlorinated polyethylene (CPE) by the solution intercalation method and their influence on mechanical properties of the nanocomposites have been studied by Kar et al. [137]. The o-MMT-embedded nanocomposites show enhanced tensile strength and Young s modulus in comparison to the nanocomposites containing the unmodified nanoclay. They have shown from and XRD analyses that organically modified clay shows better dispersion in the CPE matrix. This has been further substantiated from FTIR analysis, which proves an interaction between the CPE matrix and the clay intercalates. 

FIGURE 14.8 Comparison of interfacial adhesion of the PVC/CPE/POE trilayer and that of the POE/CPE bilayer. Each diamond and circle pair represents the strength of the bilayer or trilayer (respectively) that contains the indicated chlorinated polyethylene. Note that the similarity of the strength of each bilayer and trilayer (Eastwood and Dadmun, 2002). 

Figure 5.5 Effect of chlorine content on the glass transition temperature of chlorinated polyethylene. Data for polyvinylchloride (PVC) and polyvinylidene chloride (PVDC) are shown for comparison. Drawn after data from Schmieder and Wolf (1953).

We have recently evaluated the chlorendic imide/hindered phenol for its effect on the oxygen index of polyethylene, and we found only a miniscule increase, not considred statistically significant, in comparison to the same loading of chlorine as chlorendic anhydride. We believe that if the antioxidant approach to flame retardancy is to be successful, special high temperature antioxidant structures must be designed for this purpose. 

To get a better insight into the chlorination reaction, we wanted to avoid a heterogeneous process. Instead of polyethylene or polypropylene, we used polyisobutene, which is soluble in carbon tetrachloride, as are its chlorination products. In addition, we were interested in the structure and properties of the chlorinated products, especially in comparison with polyvinyl chloride (PVC) and vinyl chloride/isobutene (VC/IB) copolymers. 

IV 50/50 blends of chlorinated linear polyethylenes at 70 °C O one phase, two phases. The dashed curves have no theoretical background [56], The result deviates from predictions of the theory in that respect that the miscibility region expands to form bulges. The same phenomenon was observed for 50/50 blends of chlorinated branched polyethylenes (with shrinking miscibility area in comparison to linear polyethylenes) [56] and chlorinated PVCs [52]. Thus, there are conflicting results on chlorinated linear polyethylenes and chlorinated PVCs. 

Solid perfluorocarbon surfaces also have extremely low surface energies Thus, poly(tetrafluoroethylene) (PTFE, Teflon) has a y value of 18.5 dyn cm which is the reason for the anti-stick and low-friction properties used for frying pans and other applications. That this effect is directly related to the fluorine content becomes obvious on comparison of the surface energies of poly(difluoro-ethylene) (25 dyn cm ), poly(fluoroethylene) (28 dyn cm ), and polyethylene (31 dyn cm Y If only one fluorine atom in PTFE is replaced by more polarizable chlorine, the surface energy of the resulting poly(chlorotrifluoroethylene) jumps to 31 dyn cm , the same value as for polyethylene [8]. 

The comparison of polyethylene, poly(vinyl chloride), and poly(vinylidene chloride) demonstrates that the identity of the atoms in a molecule can have a tremendous impact on that molecule s properties. Let s begin our exploration by examining the structure of atoms, so that we can address the question of how a chlorine... 

The effect of solvent compatibility on chlorine distribution may be illustrated by comparison of reaction in fluorobenzene, an excellent solvent for both polyethylene and the chlorinated product, and in carbon tetrachloride, a poorer... 

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