Chemiluminescence-polymers

Hosaka S, Uchida T. Chemiluminescent polymer microspheres for measuring reactive oxygen species. In Van Dyke K, Van Dyke C, Woodfork C. eds. Luminescence Biotechnology. Boca Raton CRC Press, 2002 305-20. 

Ichimura K, Hirai T, Mizuno Y, Hosaka S. Preparation and characterization of chemiluminescent polymer microspheres for the measurement of reactive oxygen species at physiological pHs. In Preprints of the 82 annual meeting of Chem Soc Japan, Osaka, Japan 2002 141... 

G. Ahlblad, P. Gijsman, B. Terselius, A. Jansson, and K. Moller, Thermo-oxidative stablility of PP waste films as studied by imaging chemiluminescence, Polym. Degrad. Stab. 2001, 73, 15-22. 

Fan FRF, Mau A, Bard AJ (1985) Electrogenerated chemiluminescence, a chemiluminescent polymer based on poly(vinyl-9,10-diphenylanthracene). Chem Phy Lett 116(5) 400 04... 

BilUngham, N.C., Grigg, M. N. The kinetic order of decomposition of polymer hydroper oxides assessed by chemiluminescence. Polymer Degradation and Stability, 83 (2004), p. 441 - 451... 

Abruna HD, Bard AJ (1982) Electrogenerated chemiluminescence. 40. A chemiluminescent polymer based on the tris(4-vinyl-4 -methyl-2,2 -bipyridyl)ruthenium(II) system. J Am Chem Soc 104 2641-2642... 

For determination of low hydrogen peroxide concentrations, a chemiluminescent reagent system was developed consisting of oxalyldiimidazole and an immobilized fluorophore (3-aminofluoranthene) on an acrylate polymer.[47]... 

Mechanisms Leading to the Light Emission from Thermally Oxidized Polymers (Chemiluminescence), Similarities and Differences within Respective Groups of Polymers 463... 

The progress of polymer degradation may be followed by a wide variety of techniques, some of them being mentioned at the right column in the Bolland-Gee scheme (Scheme 2). There are techniques that directly monitor some of the elementary reaction steps such as, for example, oxygen absorption (reaction 2), differential scanning calorimetry (DSC) (reaction 3), chemiluminescence (reaction 11) analytical and/or spectral methods of determination of hydroperoxides, etc. 

A very fast testing of polymer stability is based on non-isothermal experiments (DSC, chemiluminescence) where the whole plot of the parameter followed may be visualized over a large temperature interval. The transfer of non-isothermal data to isothermal induction times involves a variety of more or less sophisticated approaches such as published in Ref. [8] or discussed later. 

MECHANISMS LEADING TO THE LIGHT EMISSION FROM THERMALLY OXIDIZED POLYMERS (CHEMILUMINESCENCE), SIMILARITIES AND DIFFERENCES WITHIN RESPECTIVE GROUPS OF POLYMERS... 

Emission from dimols of singlet oxygen may be detected by photomultipliers used for measurement of chemiluminescence from hydrocarbon polymers with a maximum spectral sensitivity at 460 nm. The above scheme, however, requires the presence of at least one molecule of hydrogen peroxide in close vicinity to the two recombining peroxyl radicals and assumes a large heterogeneity of the oxidation process. 

Figure 3 shows how the elementary structure of the polymer affects the observed patterns of chemiluminescence response in oxygen at 120°C. As expected, the oxidizability decreases in the order polyisoprene < polybutadiene < polypropylene < polyethylene. However, it is difficult to understand why the maximum light emission is almost 2x lower for polybutadiene than for PP. The oxidation of polybutadiene occurs via secondary peroxyl radicals, while in... 

Figure 3 Comparison of chemiluminescence runs from saturated and unsaturated hydrocarbon polymers having tertiary carbons (polypropylene, polyisoprene) in the main chain.

Recently, we have shown that non-isothermal chemiluminescence measurements for oxidized cellulose provide the same rate constants of cellulose degradation as may be measured from experiments on the decay of polymerization degree determined by viscometry. This may be also taken as indirect evidence that the light emission is somehow linked with the scission of polymer chains [29]. 

The intensity of chemiluminescence signal from a heated polymer and the kinetics of its change with time or temperature is determined by [30] ... 

The quality of the polymer, its photo-oxidation and thermo-oxidation history expressed in concentration of hydroperoxides, carbonyl groups or of other oxidized structures and terminal groups. The rate of an oxidative attack may then be related to the average molar mass and to its distribution, and to the ratio of amorphous/crystalline structures. Polymers cannot be simply ordered according to the intensity of light emission at a given temperature. The chemiluminescence-time patterns are related with the rate of sample oxidation, but they may differ from one to the next polymer. 

A direct oxidation of polymer additive, which may occasionally give a much stronger signal than the oxidation of polymer itself. This is very important as it may lead to an erroneous relation between the rate of polymer oxidation and chemiluminescence intensity. 

Qualitatively two different patterns of chemiluminescence intensity with time may be observed for polymer materials, namely,... 

Provided that chemiluminescence intensity Iql is proportional to the rate of peroxyl radicals termination, that is Icl [PO ]2, which is often assumed in the literature, chemiluminescence intensity should achieve some quasi-stationary level when hydroperoxide concentration becomes stationary and its decay should correspond to consumption of oxidizable groups, PH, in a polymer. At the same time, the chemiluminometric curves of type (a), which are typical with an autoaccelerating increase of the light emission (Figure 4) are relevant for... 

Figure 7 Arrhenius plots for non-isothermal chemiluminescence runs of oxidized polymers, (1) polypropylene, (2) polyethylene, in oxygen, heating rate 2.5°C/min. 

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