Side polymers with aromatic groups

Polymers with aromatic groups as side chains were found to form inclusion complexes with CDs. For example, a-CD was shown to complex with polymers bearing benzyl groups, while /3-CD complexed, in an efficient manner, with polymers bearing naphthalene groups [93]. 

Examination of the absorption spectra of the new polysilane materials reveals a number of interesting features (14). As shown in Table III, simple alkyl substituted polymers show absorption maxima around 300-310 nm. Aryl substitution directly on the silicon backbone, however, results in a strong bathochromic shift to 335-345 nm. It is noteworthy that 4, which has a pendant aromatic side group that is buffered from the backbone by a saturated spacer atom, absorbs in the same region as the peralkyl derivatives. This red shift for the silane polymers with aromatic substituents directly bonded to the backbone is reminiscent of a similar observation for phenyl substituted and terminate silicon catenates relative to the corresponding permethyl derivatives... 

Normally polymer structures containing aliphatic backbones are low in smokegenerating character and are generally not self-extinguishing. Additives to such systems to achieve flame-retardancy often enhances smoke generation Polymers with aromatic side groups such as polystyrene have a considerable tendency to generate smoke. 

Apparently, there will not be exhaustive results either with the chemical structure of the polymer on the preferential adsorption," or the influence of the tacticity on the preferential adsorption. In the last years, investigations regarding the effect of ortho-substituents in polymers with aromatic bulky side groups on the preferential adsorption and viscometric behavior have been reported for poly(phenyl methacrylate) and its dimethyl and diisopropyl ortho derivatives in tetrahydrofiiran/water. " Figure 5.4.5 from ref " shows the Xvalues for three polymers in THF/water. 

Polymers with aromatic side groups smoke heavily, even when flaming. The most important representative of this group is polystyrene (the conventional unsaturated polyester products are also rated here by their styrene content). 

Energy Migration in Polymers with Aromatic Side Groups(6)... 

Figure 3. Energy relaxation pathways in a polymer containing aromatic side groups following absorption of light. (Reproduced with permission from Ref. 21. Copyright 1987 Chemistry in Australia.)...

To date, much effort has been undertaken to develop new alternatives. For example, sulfonated aromatic polymers, i.e., polymers with the sulfonic acid groups directly attached to the main chain or carrying short pendant side chains with terminal sulfonic acid units, attract increasing interest because of their chemical and thermal stability, and the ease of the sulfonation procedure. Some of the proposed polymers are sulfonated polysulfone (SPSU) [134] sulfonated poly(phenylene oxide) (SPPO) [135] sulfonated poly-(ether ether ketone) (SPEEK) [136] poly(phenylquinoxaline) (PPQ) [137] and poly(benzeneimidazole) (PBI) [138],... 

Aromatic substituents are flat and one can expect compact packing facilitating the charge transfer. Therefore in compounds with substituents which are not flat photosensitivity has to be decreased. It was actually proved for polymers with bulky side groups in the ligand. Moreover, the photosensitivity was not observed in compounds 25, 26, 27 (Table 3) with bulky side groups. The same results were obtained for complexes 38 and 39 and mixed acetylenides 36, 37... 

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