Chemiluminescence-natural polymers

A number of reviews of interest have appeared of both a specific and general nature. These include photoresponslve polymers with the main emphasis on phase transitions, memory and shape retention 2 , the kinetics of polyelectrolyte formation , molecular modelling for excimer formation , luminescent probes and molecular dynamics . The uses of thermally stimulated emission for monitoring radical decay and chemiluminescence of polymers... 

The use of chemiluminescence technique has expanded to others natural polymers. Recently, Millington et al. reported studies on polymers such as the fibrous proteins wool and feather keratin, silk fibroin, and reconstituted collagen from bovine skin, which revealed new information about their degradation [81]. The potential of CL to analyze the effectiveness of treatments to protect the polymer during processing could contribute to diminish the loss of properties of the types of polymers widely used in textile industry. 

Progress in oxidation of polymers may be studied by various means FTIR, DSC, TG, SEC, CL, ESR, MALDI-ToFMS, oxygen uptake, etc. Oxylumines-cence is an effective tool for determining the extent and nature of the oxidation process of polymers at very early stages (not yet detectable by macroscopic measurements) and under conditions similar to those during service. The opportunity to study oxidation quantitatively has stimulated the application of chemiluminescence for evaluation of a broad range of materials. Applications of CL in polymer research are shown in Table 1.28. 

Luminescence can arise from two mechanisms (1) recombination of charged particles or radicals (2) mechanical excitation of units in the polymer chain. Thus, luminescence depends on the nature of the polymer, the presence of additives, and temperature. As luminescence has been found to be absent on grinding in vacuum or in an inert atmosphere, it has thus been suggested that the afterglow is a result of recombination of peroxy radicals [43]. Chemiluminescence intensity thus depends on the kind and pressure of the surrounding gas [44]. 

Kaci, M., Touati, N., Setnescu, R., Setnescu, T., Jipa, S. Characterization by Chemiluminescence of Unstabilized and HALS-Stabilized LDPE Films Exposed to Natural Weathering Conditions Int J. Polym. Anal. Charact. 9, 275-287 (2004)... 

Chemiluminescence imaging is typically performed in a light-tight chamber under nitrogen purge. In this study we included testing in air to simulate storage of polymers in the natural environment. Data acquisition time was about 5 minutes due to low count rates. 

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