Anthraquinone copolymers

In this chapter we describe the synthesis and the phase behaviour of liquid crystalline anthraquinone copolymers with different mesogenic units and azo dye-containing copolymers of the general structure ... 

For the phenylcyclohexane-anthraquinone copolymers and the biphenyl-anthraquinone copolymers examples are given in Table 1 and compared with a phenylbenzoate-anthraquinone copolymer. 

Mixtures of the Anthraquinone Monomer, the Phenylbenzoate-Anthraquinone Copolymers with the Binary Phenylbenzoate Host Mixture... 

Miscibility studies of the nematic dye-containing copolymers with suitable low molecular weight liquid crystals yield homogeneous nematic mixtures. A binary mixture of 4-cyanophenyl-4-heptylbenzoate and 4-cyanophenyl-4-pentylbenzoate is miscible with the phenylbenzoate-anthraquinone copolymers. 

Photosensitized crosslinking of polymers has been the subject of numerous publications [l - 30], concerned mainly with poly(ethylene), poly(vinyl alcohol), various vinyl copolymers, copolymers of maleic anhydride and/or phtalic anhydride with styrene and some polymers derivated from cinnamic acid. The following compounds were used as sensitizers benzophenone, 4-chloro- and 4,4-dimethylbenzophenone [l, 3-6, 8, 9l, oC -and -derivatives of anthraquinone [3, 23] acetophenone, hydroquinone, triphenylmethane and pyridine li.] chlorobenzene and no less than trichlorinated n-paraffins [6], a complex of zink chloride with o-dia-nizidine fill potassium bichromate [l2j, anthracene fl3, 14] 2,5-methoxy-4-amino-trans-stilbene [l5], benzyl ideneacetophenone fl6-l8] -thiophenylacetophenone,... 

It is also possible to form graft copolymers on the surface of fibers by coating them with photoinitiators, like benzophenone, together with a monomer and then irradiating them with ultraviolet light. Similar to the action of the anthraquinone dyes shown above, benzophenone in... 

Flectol H. See 2,2,4-Trimethyl-l, 2-dihydroquinoline polymer Flectol ODP. See p,p -Dioctyldiphenylamine Flectol TMQ. See 2,2,4-Trimethyl-1,2-dihydroquinoline polymer Fleetquest 8800. See Anthraquinone Fleshing grease, sulfated sodium salt. See Sodium tallow sulfate Flexalloy. See Polyvinyl chloride Flexan 130. See Sodium polystyrene sulfonate Flexathene TP 1300-HC, Flexathene TP 4300-HR, Flexathene TP 4390-HU. See Propylene/ethylene copolymer Flexbond 20, Flexbond 25, Flexbond 28, Flexbond 28S. See Acrylic resin Flexbond 149, Flexbond 150, Flexbond 153, Flexbond 165. See Polyvinyl acetate Flexbond 274, Flexbond 277, Flexbond 289. See Acrylic resin... 

PTs 244 [437], 245 [438], and 246 [439] with pendant anthraquinone or tetracyanoanthraquinodi-methane moieties have been synthesized as possible active materials PV devices. The polymers were reported to be soluble and to exhibit a photoinduced electron transfer process in solution. Photoinduced electron transfer from PT to phthalocyanine units was observed in copolymer 247 [440]. 

In addition there is a report of a water soluble polymeric (copolymer) photoinitiators. These initiators were synthesized by copolymerizing 2-acryloxy and 2-acrylamido anthraquinone monomers with three water-soluble comonomers acrylamide, 2-acrylamido-2-methylpropane sulfonic acid and 2-acryloxyethyl trimethylammonium iodide. The polymerization activity correlates well with their measured photo reduction quantum yields in water... 

Fig. 8. Molecular structure of typical dyed copolymers with (a) an azo dye moiety and (b) an anthraquinone side-group.

Andrieux, C. R, and Audebert, R, Synthesis and cyclic voltammetry of pyrrole copolymers substituted by anthraquinone, phenothiazine or anthracene moieties, J. Elec-troanal. Chem., 285, 163-175 (1990). 

Sulfamation of some of the residual amines with trimethylamine-SOo complex extends the water solubility of the i>olymeric dyes to basic pH ranges. An alternate route to such water soluble polymeric dyes is through the binding of the anthraquinone dyes to copolymers of vinylamine and vinyl sulfonic acid. 

The phenylbenzoate copolymers with the anthraquinone dye form nematic phases which decrease with increasing content of the dye monomer as shown in Fig. 2. The copolymer with an anthraquinone monomer content of about 39 % by weight is no longer liquid crystalline. 

Mixtures of the Anthraquinone-Containing Copolymers with Low Molecular Weight Liquid Crystals... 

By using copolymers with different dye compositions it is possible to reduce the copolymer content in the mixture while retaining a constant dye concentration. It should be noted that the value of 1 5 % (by weight) is not the maximum dye content for these mixtures. In low molecular weight guest-host systems derivatives of this type of anthraquinone dye are less soluble than 1 % (by weight) in several nematic hosts. ... 

The measurements show that the order parameters of the dissolved anthraquinone monomer are higher (5d = 0-61) at low temperatures (30-9 °C) than those of a mixture of copolymer 2 (5d = 0 58) in the same low molecular weight host. It is interesting to note, however, that the temperature dependence of the order parameter of the polymer system is lower. At 47-3 °C both systems show the same order parameter = 0 51). The temperature dependence of the order parameters for both systems is shown in Fig. 5. 

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