Poly soluble derivatives

Fullerene Cgo also functions efficiently as an antioxidant, actually being better than other lipid-soluble antioxidants at scavenging reactive oxygen species (ROS) (Wang et al., 1999). Water-soluble derivatives of C o, such as a poly-hydroxyl form, are able to function in the same respect in aqueous environments. 

Various commercial suppliers now offer fullerene derivatives with functionalities available for bioconjugation, including carboxylic and poly-hydroxylic derivatives, which are very hydrophilic and water-soluble (BuckyUSA, NanoLab, NanoNB, Nano-C, and Aldrich). 

Water-soluble derivatives of polythiophene have been made allowing counterions bound to the polymer backbone to self-dope with the protons (e.g., lithium and sodium ions) injecting electrons into the pi-system. Thus, combinations of sodium salts and proton salts (e.g., prepared from poly-3-(2-ethanesulfonate)thiophene) have been prepared that are both water-soluble and conducting. 

Partially substituted derivatives of polyacetylene are synthesized via the ring-opening metathesis polymerization (ROMP) of cyclooctatetraene (COT) and its derivatives. Certain poly-COT derivatives afford soluble, highly conjugated poly acetylenes. These materials exhibit large third-order optical nonlinearities and low scattering losses. 

Another type of noncovalent interaction, namely electrostatic ones, has recently been exploited by Wang et al. in the fabrication of a hybrid film containing a water-soluble poly(thiophene) derivative and CdSe NCs.141 In this case CdSe NCs were functionalized with 11-mercaptoundecanonic acid (MUA) molecules prior to their self-assembly with side chain-functionalized poly(thiophene), that is, poly(3-(3 -thienyloxy)propyltrimethylammonium bromide) (P3TOPA). 

Several organics, e.g. pristine poly(3-octylthiophene), polyfluorene, bifunctional spiro compounds and polyphenyleneethynylene derivative, have been used for fabricating photOFETs. Responsivity as high as 0.5-1 A/W has been achieved in some of these transistors. We have already discussed the bulk heterojunction concept in Chapter 5. The bulk heterojunctions are fabricated using acceptor materials with high electron affinity (such as C<5o or soluble derivatives of C6o) mixed with conjugated polymers as electron donors. PhotOFETs based on conjugated polymer/fullerene blends are expected to show... 

Miller Radiation Sensitivity of Soluble Poly silane Derivatives... 

Poly(phenylene vinylene), PPV, and its soluble derivatives have emerged as the prototypical luminescent semiconducting polymers. Since PPV has a nondegenerate ground state, structural relaxation in the excited state leads to the formation of polarons, bipolarons, and neutral excitons. However, prior to treating the structural relaxation in the excited state, one needs to develop a satisfactory description of the electronic excited states. 

Despite the extensive photoconductivity data, the nature of photoexcitations in poly(phenylenevinylene), PPV, and its soluble derivatives has remained controversial. In part, the controversy arises from the conflict between the results obtained with fast time-resolved photoconductivity and those obtained by the more familiar steady-state photoconductivity the latter indicate a strong T-dependence for the np product. Recent experiments have resolved the apparent conflict [203]. The idea is rather simple If the sample is sufficiently thin that the photocarriers can be swept out before a significant fraction fall into traps, the steady-state photocurrent will provide information similar to that obtained at short times by transient photoconductivity (in the latter, sample thickness is not important since pre-trapping and trap dominated transport are separated in the time domain). 

To extend Whiteside s method, it is possible to synthesize ligands containing hydroxyl, ether, or carboxyl groups [13], e.g. acid chlorides or anhydrides containing polyethylene glycol), poly(ether) or poly(hydroxyalkyl) chains. In Scheme 3 [12], the use of this method to synthesize water-soluble derivatives of the DIOP ligand is displayed [14, 15],... 

Melamine is soluble only in water and has low solubility in dimethylsulfoxide (DMSO) and in other aprotic dipolar solvents (9% at 120 °C), in glycerol or ethylene glycol (10% at 140 °C). In the majority of other usual solvents it is insoluble. Kucharski and Lubczak discovered a new class of reactive solvents for melamine [36] poly (hydroxymethyl) derivatives of cyclohexanone, acetone, nitromethane which are able to dissolve 50-60% melamine. Melamine can be totally propoxylated or ethoxylated at lower temperatures (70-90 °C), in aprotic dipolar solvents (for example DMSO, dimethylformamide, N-methyl pyrrolidone and so on), in the presence of quaternary ammonium hydroxides as catalysts [for example tetrabutyl ammonium hydroxide (TBAH)], at a low reaction rate (reaction 15.35), for a very long reaction time (40-50 hours) [31, 37]. The resulting hexafunctional polyols give very thermostable rigid PU (up 200 °C). 

Polyamides are well-known industrial products having applications in many areas (7). For instance, the Nylon polymers (water-insoluble polyamides) are widely used in fibers. A water-soluble poly(aminoamide), derived from adipic acid and diethylene triamine, is the precursor to a well-known industrial resin (2). This poly(aminoamide) is currently produced by a chemical reaction at elevated temperatures which is accompanied by the formation of some branched structures. Subsequent derivatization of this polyamide produces a water-soluble resin, known for its ability to impart wet strength to paper and paper products (2a, 2b) and shrink proofing to wools and other textiles (2c). 

Insolubility and infusibility of poly acetylene make it impossible to determine its molecular weight by the usual methods based on solutions. Several attempts have been made either to convert polyacetylene to soluble derivatives in order to measure their molecular weight... 

By 1995 one finds that the main actors are different polymers, a change which can be partly attributed to the recent interest in semiconductor properties, especially light emission. In the field of conduction, polyacetylene has given its place to polyaniline, a polymer with a fascinating rich chemistry and a promise of good processability. In the semiconductor arena, the most studied polymer of the past decade is polythiophene, or rather its soluble derivatives which lend themselves very well to various fabrication processes. Another polymer, one which was only mentioned briefly in the 1986 Handbook, is competing with polythiophene for application in semiconductor devices poly(pura-phenylene vinylene). These three polymers received very little interest before 1985 no crystallographic studies had been published at that time. 

To improve the limit-of-detection, we replaced the 16 mm vacuum deposited CuPc/Cgg bilayer devices with 1 mm solution-processed polymer devices based on 1 1 blends by weight of poly(3-hexylthiophene) [P3HT] and [6, 6]-phenyl-C61-butyric acid-methylester [PCBM] - a soluble derivative of Ceo- The P3HT PCBM devices fabricated in our laboratory typically have very low short-circuit dark current densities of <10 mA cm , and are consequently a good choice for high sensitivity detection [21]. The... 

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