Degradation behavior of polymer

In the polymer industry, the melting or degradation behaviors of polymers are important to determine. For example, when a polymer is extruded (i.e., when polymer pellets are converted to film by heating them and drawing them through an extruder), the thermal analysis of the polymer material determines the amount of heat needed in the extruder to make the material pliable. Given the large number of polymer formulations that have been developed and continue to be developed, thermal analysis procedures can be quite important. 

Jang, B. N., Costache, M., and Wilkie, C. A. The relationship between thermal degradation behavior of polymer and the fire retardancy of polymer/clay nanocomposites, Polymer (2005), 46, 10678-10687. 

The authors and the editors sincerely hope that this overview will improve the understanding of the degradative behavior of polymers and will assist our fellow research and development scientists in their pursuit of improved materials. 

Incompatible polymer blends are heterogeneous, but only the compatible blends (on a molecular scale) are homogeneous. Both the structure and the presence of different chemical species are important points in the degradation behavior of polymer blends and strongly differentiate the degradation of these polymeric systems from that of pure, homogeneous materials. 

All the discussed blends are incompatible, and their heterogeneous nature could be responsible for their peculiar degradation behavior. Since most polymers are immiscible, the influence of compatibility on the degradation behavior of polymer blends has not been extensively studied. Moreover, some contrasting results have been reported. Refer to Polyblends. 

Luo, M., Huang, C., Liu, W. et al. 2010. Degradation behaviors of polymer electrolyte membrane fuel cell under freeze/thaw cycles. International Journal of Hydrogen Energy 35 2986-2993. 

This type of SEC-MS hyphenation has been applied to a wide variety of homopolymers and copolymers amongst them are polyacrylates, polyesters, polyethers, polyamides, resins, polycarbonates, proteins, and polystyrene. Synthesis optimization, investigation of the degradation behavior of polymers, polymer aging, and deformulation have been the goals of the analysis. 

These interactions can take place in the interfacial regions of the phases. That is why the degradation behavior of polymer blends cannot be predicted on the basis of the degradation behavior of their individual components. Both synergetic as well as antagonistic effects are observed here [595]. 

Thermal and Oxidative Degradation Behavior of Polymers and Nanocomposites... 

K.N. Lewis, M.V. Thomas, D.A. Puleo, Mechanical and degradation behavior of polymer-calcium sulfate composites, J. Mater. Sci. Mater. Med. 17 (2006) 531-537. 

In the past few decades, piperidine-based sterically hindered amine stabilizers (HA(L)S) gained attention as heat stabilizers for polyolefins at low and moderate temperatures below about 120 °C. It was ascertained that the degradation behavior of polymers, particularly of polyolefins stabilized with HA(L)S, differs significantly from that of phenol-stabilized polyolefins at aging temperatures ranging from T = 100 to 150 °C. 

The effect of substitution of labile chlorines by acetoxy groups on the thermal stability of polymer taken in isolation appears to correspond to the thermal degradation behavior of VCA Ac copolymers over the whole composition range [136,137]. 

For the purpose of illustration, let us consider the degradation behavior of a hypothetical monodisperse polymer fraction flowing along the central streamline. 

Du LC, Meng YZ, Wang SJ, Tjong SC (2004) Synthesis and degradation behavior of poly (propylene carbonate) derived from carbon dioxide and propylene oxide. J Appl Polym Sci 92 1840-1846... 

The thermal degradation behavior of the mixtures can be explained by the assumption that in chloroparaffin-polymer blends, chlorine radicals that propagate the dehydrochlorination in the chloroparaffin domains can migrate in the polymer phase where they abstract hydrogen atoms from the polymer backbone ... 

Salaneck [3] presented in the mid-1980s a fine review on the application of photoelectron spectroscopic techniques to the study of electroactive polymers. However, a substantial number of new and significant XPS studies have since appeared, in conjunction with the ever increasing research on new families of electroactive polymers. This is particularly true for aniline polymers and some polyheterocycles. Thus, updating XPS work on electroactive polymers appears to be appropriate. This review will focus mainly on XPS core-level spectra, with some references made to valence band spectra. First, a brief description of the basic principles of XPS is presented for readers who are less familiar with this technique. Next, the type and level of information that its application provides for the elucidation of the intrinsic structure, the CT interaction, and the stability and degradation behavior of each family of electroactive polymers are presented and discussed in detail. Finally, some future directions for the applications of... 

Recently, we have reported that the degradation of crosslinked UPs in SCW was enhanced by adding alcohols with a long alkyl chain (8) and amines (9). In this paper, we report the degradation behavior of a crosslinked UP using SCW treatment in the absence and presence of the additives and propose a new recycling system of polymers. 

The MW of polymers of aliphatic disubstituted acetylenes such as 2-octyne remarkably reduces, when such polymers are irradiated with y-rays in airll7) (Fig. 10). In contrast, polymers of aromatic disubstituted acetylenes like 1-phenyl-1-propyne hardly degrade by y-rays irradiation in air. Thus the degradation behavior of substituted poly acetylenes is greatly dependent on the kind of substituent. The mechanism is essentially the same as that for thermal degradation. 

Yu, F. Zhuo, R. Synthesis, characterization, and degradation behaviors of end-group-functionalized poly(trimethylene carbonate)s. Polym. J. 2003, 35 (8), 671-676. 

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