Phthalocyanine content

Hydroquinone, catechol and benzoin were also found to drastically reduce the temperature and time required for the polymerization of I, increase the phthalocyanine content of the polymer (II), and improve its thermal stability. For example, without additive, I required 80 hours of heating at 300°C to effect an 87% reaction of CN groups. However, a stoichiometric mixture of I and hydroquinone underwent 88% reaction when heated at 165°C for 2 hours followed by 250°C for 1 hour. With added catechol, DSC (Fig. 2) carried out isothermally at 202°C showed a well defined exotherm indicating complete cure after 27 minutes. Bulk samples of the polymer (II) cured with these... 

In conclusion, the bis-phthalonitrile (I) can be polymerized at moderate temperatures and short reaction times to a network polymer having a high metal free phthalocyanine content by employing a suitable co-reactant. 

Phthalocyanine content was determined by electronic absorb-tion at 697 nm (dioxane). Analytically pure samples of VII were used to generate a calibration curve which was then used to deter--mine the amount of phthalocyanine chromophore generated from reactions of VI and also of I. 

Copper Phthalocyanine grades are also supplied as special-purpose types with a limited or defined free copper content, targeted for the coloration of rubber (see p. 444). 

The oxidation of starch in aqueous suspension with H202 in the presence of iron phthalocyanine gives both carboxylic and carbonyl groups (Table 3.1). The best yields were obtained with a molar ratio 12900/1 (0.0078 mol%), but the oxidation was still quite efficient with 0.0039 mol% of catalyst [25800 per anhydroglucose unit (AGU)/catalyst ratio]. The oxidized starch had almost the same final Fe-content as the initial potato starch. Still, the efficiency of this method in view of scaling up was limited by comparatively low activity and product isolation problems. 

The protons released are presumably available to compensate for the loss of the charge balancing cations within the zeolite. In conventional syntheses, the phtha-lonitrile condensation normally requires the nucleophilic attack of a strong base on the phthalonitrile cyano group [176, 177]. This function is presumably accommodated by the Si-O-Al (cation) basic sites within the ion-exchanged faujasite zeolites [178, 179]. The importance of this role is perhaps emphasized by the widespread use of alkali metal exchanged faujasites, particularly the more basic NaX materials of higher aluminium content [180, 181] as hosts for encapsulated phthalocyanine complexes. 

Further evidence has been obtained to support the contention that the active catalysts are metal complexes dissolved in solution. With experiments reported in Table II, the kinetics of oxidation under standard conditions in the presence of various metal salts are compared with the rates of reaction when solid residues have been filtered from solution. The agreement between the rates in Cases 1 and 3 of Table II (where the amount of metal available is dictated by the solubility of metal complexes) shows that solid precipitates play little or no part in catalysis in all the systems studied. The amount of metal in solution has been measured in Cases 2 and 3 metal hydroxide complexes (Case 2) are not as soluble as metal-thiol complexes, and neither is as soluble as metal phthalocyanines (19). The results of experiments involving metal pyrophosphates are particularly interesting, in that it has previously been suggested that cobalt pyrophosphates act as heterogeneous catalysts. The result s in Table II show that this is not true in the present system. 

Copper phthalocyanine (50 g) in 120g of 6N sulfuric acid was mixed and evaporated to dryness. The product was grinned and heated to 180-190°C for 2 hr to obtain 47 g product with a sulfur content of 8.12%. A sulfonated copper phthalocyanine containing 1.3 groups/ mol is obtained, heating 32.7 g 75% 4-sulfophthalic anhydride and 25% 3-sulfophthalic anhy-... 

Due to the great potential applications and the widespread interests of OFETs, several review articles with emphasis on different aspects of OFETs have been published [8-13], However, despite the extensive studies and increasing research interests in phthalocyanine as well as porphyrin semiconductors, there is still no review article that systematically generalizes the research achievements in the field of tetrapyrrole organic semiconductors for OFETs. Thus, the present contribution should interest scientists in both industrial and theoretical fields. The main contents of this chapter is as follows Firstly, some basic introduction of the structure and characteristics of OFET is provided then theoretical factors that influence the performance of OFET devices is discussed finally, the progress in phthalocyanine-based OFETs in the order of p-type, n-type, and ambipolar semiconductors is summarized. 

The chemical structure of iron-phthalocyanine is shown on Figure 1. PcFe is a planar molecule with a central cavity in which the iron atom is located. Metal phthalocyanines may be sublimated and the deposition of PcFe on the carbon support has been done by vapor phase condensation (16). During the condensation, the carbon supports are kept at 235°C, Condensation rates were in the range 2-4 mg PcFe per hour. Samples with PcFe content ranging from 0.5 to 30 % in weight have been prepared with both carbon substrates. 

As antiscuff, anti-wear properties of additives depend on the covalent-bonded sulfur contents, the selection of optimum conditions to effect sulfuring processes has been set with introducing the greatest amount possible of covalent sulfur. For this purpose functionalizing of diene and olefin hydrocarbons was conducted on a wide time-temperature mode. Considering that the temperature of boiling pipeiylene fraction low (42-44°C), sulfuring was carried out in a constantly temperature-controlled autoclave in the presence of the catalyst cobalt phthalocyanine [3], in the medium of non-polar solvents (for example, heptane). Under... 

Reaction of VI with Various Additives (Table II). Compound VI (0.5 mmol) and 0.125 mmol of the additive were placed in sealed tubes and heated at 165°. The tubes were initially monitored in terms of change from a fluid to solid and those which solidified were opened and the i r spectra taken to determine the extent of reaction. Those samples which had not undergone sufficient reaction were resealed and reheated. When the i r showed that sufficient reaction had occurred, the contents were analyzed for phthalocyanine chromophore content. 

Isobutyraldehyde (1.27ml 14 mmol), olefin (4 mmol), 1,2-dichloroethane (25 ml) and manganese phthalocyanine (0.7 mmol, 5 mol % of aldehyde) were stirred under oxygen atmosphere (balloon) for 3 h. After work-up as in the sulphide oxidation the reaction mixture was analysed by GC for olefin and epoxide contents. The epoxides were identified by comparing the retention times with authentic samples prepared by literature method[12]. These results are presented in Table-2. No efforts were made to optimize the yields of epoxides, by varying the reaction time. 

Analysis of the iron content allowed determination of the amount of iron phthalocyanine present in the zeolite. It was found that the metal macrocycle content of the zeolite was 0.02 mmol Fe(Pc)/g catalyst. The I.R. and the nitrogen analysis data showed, that the amount of Ho-phtnalocyanine was much higher than the amount of Fe(Pc), just as it was published by Parton and coworkers [10]. This is not surprising, because 1,2-dicyanobenzene was used in large excess over ferrocene. 

The dependence of the initial rate of oxidative decarboxylation of oxalic acid on the total acid concentration and the content of undissociated species of mono- and dianion in aqueous solutions in the presence of polymeric cobalt phthalocyanine has been examined [160]. Whereas the monoanion, [HC2O.C], of oxalic acid is shown to enter the reaction, the undissociated species does not. Furthermore, [C204 ] dianion retards the process. This is attributed to the fact that in catalyst A, active particles of CoPc(NaS03)4 are located mainly on the species surface while in catalyst B they are distributed within the species and are hardly accessible. 

Synthesis of the incorporated phthalocyanine Ludox As 40 (92.5 g), tetraethylammonium hydroxide (92.5 g of a 20 wt.% solution in water) and deionized water (75 g) were placed in a polypropylene vessel and stirred at room temperature for 22 h. A mixture of CTAC (5 g of a 25 wt.% solution in water) and one of the phthalocyanines ( 300 mg, -0.25 mol) was added slowly (5 mL min ) to gel (10.4 g) with stirring. This mixture was stirred for 15 min and aged overnight at room temperature. The composition of the final gel mixture was 9.61% SiOz, 4.8% TEAOH, 77.47% H2O and 8.12% CTAC. The mixture was reacted without stirring for 40 h at 100 °C in a polypropylene autoclave. The resulting green product was recovered by filtration and washed intensively with water and hot ethanol. The MCM-41 structure was proven by X-ray diffraction. The content of the phthalocyanine in the molecular sieve is -10 mol g. ... 

At the lowest velocity 100 m/min inside fibres the crystalline structure consisting of both polymorphic modifications is formed. The K value equals 0.75. The content of p crystals is much higher than the content of a crystals. Nevertheless, the content of the p form is much lower in comparison to fibres coloured with quinacridone alone, but significantly greater in comparison to fibres coloured with phthalocyanine (Broda, 2003d). 

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