Bisphenol analysis

For the above reaction to occur, the aromatic nuclei in compound 1 should carry activating groups, such as hydroxyl, alkoxy, or fused ring aromatics". As a result of reaction with BF3 and phenol, the macromolecular structure of coal should undergo rupture at the aliphatic bridges, and these bridges are transferred to phenol molecules to produce bisphenols. Analysis of the bisphenols should provide information on the aliphatic bridges present in coal structure. 

A difunctional bisphenol-A-based benzoxazine has been synthesized and characterized by GPC and 1II NMR (Fig. 7.39). A small of amount of dimers and oligomers also formed. Thermal crosslinking of bisphenol-A benzoxazine containing dimers and oligomers resulted in networks with relatively high Tgs. Dynamic mechanical analysis of the network showed a peak of tan 8 at approximately 185°C. 

Staples, C.A. (1998). Analysis of Surface Water Receiving Streams for Bisphenol A Manufacturing and Processing Sites, Technical Report to Bisphenol A TaskGroup by the Society of the Plastics Industry, Inc., Washington, D.C. 

Blends of enzymatically synthesized poly(bisphenol-A) and poly(p-r-butylphenol) with poly(e-CL) were examined. FT-IR analysis showed the expected strong intermolecular hydrogen-bonding interaction between the phenolic polymer with poly(e-CL). A single 7 was observed for the blend, and the value increased as a function of the polymer content, indicating their good miscibility in the amorphous state. In the blend of enzymatically synthesized poly(4,4 -oxybisphenol) with poly(e-CL), both polymers were miscible in the amorphous phase also. The crystallinity of poly(e-CL) decreased by poly(4,4 -oxybisphenol). 

While additive analysis of polyamides is usually carried out by dissolution in HFIP and hydrolysis in 6N HC1, polyphthalamides (PPAs) are quite insoluble in many solvents and very resistant to hydrolysis. The highly thermally stable PPAs can be adequately hydrolysed by means of high pressure microwave acid digestion (at 140-180 °C) in 10 mL Teflon vessels. This procedure allows simultaneous analysis of polymer composition and additives [643]. Also the polymer, oligomer and additive composition of polycarbonates can be examined after hydrolysis. However, it is necessary to optimise the reaction conditions in order to avoid degradation of bisphenol A. In the procedures for the analysis of dialkyltin stabilisers in PVC, described by Udris [644], in some instances the methods can be put on a quantitative basis, e.g. the GC determination of alcohols produced by hydrolysis of ester groups. 

Extraction or dissolution almost invariably will cause low-MW material in a polymer to be present to some extent in the solution to be chromatographed. Solvent peaks interfere especially in trace analysis solvent impurities also may interfere. For identification or determination of residual solvents in polymers it is mandatory to use solventless methods of analysis so as not to confuse solvents in which the sample is dissolved for analysis with residual solvents in the sample. Gas chromatographic methods for the analysis of some low-boiling substances in the manufacture of polyester polymers have been reviewed [129]. The contents of residual solvents (CH2C12, CgHsCI) and monomers (bisphenol A, dichlorodiphenyl sulfone) in commercial polycarbonates and polysulfones were determined. Also residual monomers in PVAc latices were analysed by GC methods [130]. GC was also... 

As to the main limitation of MS vs. FTIR detection, namely the inability to distinguish closely related isomers, this rarely plays a role in additive analysis. Notable examples of isomeric additives are the bifunctional stabilisers C22H30O2S as 4,4 -thio-bis-(6-t-butyl-m-cresol), 2,2 -thio-bis-(4-methyl-6-f-butylphenol) and 4,4 -thio-bis-(2-methyl-6-f-butylphenol) (Section 6.3.6), the bisphenolic antioxidants C23H32O2 (Plastanox 2246 and Ethanox 720) and the phenolic antioxidants C15H24O (nonylphenol and di-f-butyl-p-cresol). 

Analysis of potential endocrine disrupters, such as alkylphenols (degradation products of non-ionic surfactants), diphenolalkanes (cumylphenol, bisphenol-A, bisphenol-F) and benzophenones (from the paper industry) with RPLC-SSI-QITMS in the negative ion mode has been described [631]. 

Recently, several reports of the flame-retardant properties of boron-containing bisphenol-A resins have appeared from Gao and Liu.89 The synthesis of a boron-containing bisphenol-A formaldehyde resin (64 and 65) (Fig. 42) from a mixture of bisphenol-A, formaldehyde, and boric acid, in the mole ratio 1 2.4 0.5, has been reported.893 The kinetics of the thermal degradation and thermal stability of the resins were determined by thermal analysis. The analysis revealed that the resin had higher heat resistance and oxidative resistance than most common phenol-formaldehyde resins. 

The MALDI spectrum of a polymer sample in which all chains possess the same backbone allows identification of the end-groups present at the chain ends. This type of analysis is referred to as end-group analysis. An example will be helpful. Figure 15.1 reports the MALDI spectrum of a poly(bisphenolA carbonate) (PC for short) sample [7], It displays a series of peaks from 2 up to 16 kDa, the most intense ones in the region from 5 up to 7 kDa. It also displays peak assignment and an expansion of the spectral region from 3.0 up to 3.7 kDa. Peaks at 3034, 3288, and 3542 are labeled as A and are due to PC chains terminated with phenolcarbonate on both sides. Peaks at 3168, 3422, and 3676 are labeled as B and are due to PC chains terminated with phenolcarbonate on one side and bisphenol-A on the other. Peaks at 3048, 3302, and... 

Figure 15.1. MALDI spectrum of a polycarbonate sample along with peak assignment. In the inset, an expansion of the spectral region from 3.0 up to 3.7 kDa is shown. (Reproduced from Puglisi, C. et al., 1999. Analysis of Poly(bisphenol A Carbonate) by Size Exclusion Chromatography/Matrix-Assisted Laser Desorption/lonization. I. End Group and Molar Mass Determination. Rapid Communications in Mass Spectrometry, 13 2260-2267. With permission of John Wiley Sons, Inc.)...

Bromide analysis, of water, 26 41 Bromide ions, in development solution, 79 205-206 Bromides, 4 319-330 thorium, 24 763 titanium, 25 54 tungsten, 25 379 uranium, 25 439 Bromimide, 4 299, 319 Brominated additive flame retardants, 77 461-468, 471-473t Brominated Anthanthrone Orange, pigment for plastics, 7 367t Brominated aromatic compounds, 7 7 459 Brominated bisphenol A-based epoxy resins, 70 366... 

In the absence of co-reactants, it is supposed that the polymerization is promoted by traces of water or other nucleophiles, since very pure monomer does not gel even after extended heating. Conversely, gelation may be accelerated by addition of phenols such as bisphenol A. Dynamic mechanical analysis of cured resins confirms that they are practically identical whether or not the phenol is added. 

Polymerization Method. To a solution of 5.18 mmole of HFB or PFB and 5.18 mmole of the appropriate bisphenol or bisthiophenol in 20 ml of solvent was added 22.4 mmole anhydrous of K2CO3 and 1.43 mmole of 18-crown-6 ether. The magnetically stirred, heterogenous mixture was heated in an oil bath and maintained under N2. Upon cooling to room temperature, the mixture was slowly poured into ca. 150 ml of methanol and was vigorously stirred. The filtered solids were washed three times in a blender with 300-ml portions of distilled water. The solids were air dried and subsequently placed in a vacuum oven (80 ) for 24 hr. Where soluble, the polymers obtained were characterized by IR and PMR analysis. Elemental analyses for all polymers were satisfactory. Polymer solubility was determined in THF, DMF, dioxane, toluene, m-cresol, chloroform, and sulfuric acid. The percent insoluble polymer was determined gravimetrically. Inherent viscosities of soluble polymers were determined in ca. 0.5% wt. solutions in either chloroform or THF. 

Analytically, epoxy groups are determined by the reaction with hydrogen halide and back titration with a standard base. Other functional groups present may cause interference problems and result in poor end points. Pyridinium chloride-pyridine is a recommended reagent for the analysis of bisphenol-diglycidyl ether resins [22,23],... 

The complex sorption behavior of the water in amine-epoxy thermosets is discussed and related to depression of the mechanical properties. The hypothesized sorption modes and the corresponding mechanisms of plasticization are discussed on the basis of experimental vapor and liquid sorption tests, differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and dynamic mechanical analysis. In particular, two different types of epoxy materials have been chosen low-performance systems of diglycidyl ether of bisphenol-A (DGEBA) cured with linear amines, and high-performance formulations based on aromatic amine-cured tetraglycidyldiamino diphenylmethane (TGDDM) which are commonly used as matrices for carbon fiber composites. 

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