Calibre® polycarbonate

Cadox Organic peroxides, Akzo Calibre Polycarbonate resins, Dow Capran Nylon films, AlliedSignal Capran Unitlraw Uniaxially oriented nylon film, AlliedSignal Capron Nylon resins and compounds, AlliedSignal... 

Calibre Polycarbonate Resins Product Information Guide, Dow Plastics. 

Houben [256] has compared the determination of flame-retardant elements Br, P, S, K, Cl and F in polycarbonate using commercial (X40 and UniQuant ) software. For the X40 method, a calibration line for each element in PC or PC/ABS blends was mapped for the conversion of intensities to concentrations. With the universal UniQuant method, sensitivity factors (ks) were calibrated with pure standards. The X40 method turned out to be more reliable than UniQuant for the determination of FRs in PC and PC/ABS blends, even in the case of calibration of k values with PC standards. Standard errors of 5 % were achieved for Br, P, S and K, and 20% for Cl and F the latter element could not be determined by means of UniQuant (Table 8.44). GFR PC cannot be quantified with these two methods, because of the heterogeneous nature of the composites. Other difficult matrices for XRF analysis are PBT, PS and PP compounds containing both BFRs and Sb203 (10-30wt %) due to self-absorption of Sb and interelement effects. 

Polycarbonates are an unusual and extremely useful class of polymers. The vast majority of polycarbonates are based on bisphenol A [80-05-7] (BPA) and sold under the trade names Lexan (GE), Makrolon (Bayer), Calibre (Dow), and Panlite (Idemitsu). BPA polycarbonates [25037-45-0]> having glass-transition temperatures in the range of 145—155°C, are widely regarded for optical clarity and exceptional impact resistance and ductility at room temperature and below. Other properties, such as modulus, dielectric strength, or tensile strength are comparable to other amorphous thermoplastics at similar temperatures below their respective glass-transition temperatures, T. Whereas below their Ts most amorphous polymers are stiff and britde, polycarbonates retain their ductility. 

The response times and washout times of electrodes fabricated from these materials are, respectively, <30 s and <50 s but the linear calibrations are restricted, e.g. 0.1-5 mM for the polycarbonate electrode. 

Analysis schemes developed for identifying clay minerals in the TEM based on EDS spectra (e.g., Murdoch et al.100) are inappropriate for colloidal samples dispersed on polycarbonate filters due to complications associated with the various sample-beam-substrate interactions that differ dramatically from that of ideal samples or standards with smooth polished surfaces.94 96 101 102 Correction procedures that account for the influence of particle size and morphology on x-ray spectra have been widely available for some time,101102 but these techniques have not been applied to the analysis of environmental particulates. To overcome the limitation of quantitative elemental analysis, some research groups have compared the x-ray spectra for sample colloids to the spectra for various minerals of similar size and composition under the same instrumental and sample preparation conditions to calibrate instrumental response.7 24 93 Noting the resolution problems associated with SEM analysis of submicron colloids, several research groups have chosen TEM as the primary discrete particle analysis technique,21 52 103 104 or have combined TEM analysis techniques, such as electron diffraction and x-ray microanalysis, to confirm conclusions drawn from SEM surveys.7,93 105... 

Typical molecular weights of all synthesized copolymers were in the range of 22,000-33,000 g/mol with polycarbonate standards used for calibration. These slight differences in molecular weights did not produce detectable changes in solvent-resistance for the same copolymer compositions as determined by traditional solvent-resistance measurements.16... 

Calibre. [Dow Plastics] Polycarbonate resin engineering thermoplastic for food contact, medical, transportation, appliance, housewares, business machines, recreation, and service industries. 

Molten polyesters show low viscosity and small extmdate swell. For these reasons, they have been blended with amorphous polymers to improve the latter s processability and chemical resistance. Elastomers have also been added to polyesters to improve impact resistance. Blends of polyester (either PET or PBT) with polycarbonate, PC, are the most popular (viz., Bay/oF, BCT4201, Calibre , Dialoy P, Ektar MB (with PCTG), Idemitsu SC, MakroblencT, MB4300, NovadoF, Pocan , R2-9000, Sabre , SC 600, Stapron E, Ultra-blencF KR, Valox , Xenoy 1000, etc.). Presence of PC in PET/PC increases crystallization rate of PET, which translates into faster injection molding cycle and lower part distortion upon demolding than those observed for neat PET. 

Use of the a-relaxation of amorphous polymers as a standard A simple method to calibrate the temperature is to compare the loss peaks related to the glass-transition dynamics (a-relaxation) of pure amorphous polymers, obtained in a well calibrated apparatus, with the data obtained in the paratus in which the temperature is not calibrated. The calibration tests in the uncorrected equipment must be done under similar conditions (e.g. heating rate) to the ones that are to be performed in future experiments using that equipment. This method was tested using polycarbonate films [30], where a global comparison between the different strategies proposed in this section is also discussed. 

Calibre Dow Chemical s trade name for its family of polycarbonate plastics. 

Figure 2.6 shows the calibration curves for poly(n-butyl methacrylate) (PnBMA), poly(decyl methacrylate) (PDMA), poly(methyl methacrylate) (PMMA), poly(ferfbutyl methacrylate) (PtBMA). It can be seen that the lines are almost parallel to each other, which implies that the slope hi is approximately constant, whereas bo varies. The changes in bo correspond to a change in the molar mass, and they may be quite large. For instance, when tetrahy-drofuran (TUF) is used as a solvent, polystyrene (at a given elution volume) has a mass tirat is about two times the mass of polycarbonate. It can be concluded that every polymer has its own calibration line, corresponding to a specific set of values for bo and b in Eq. 2.25. 

Calibre 2060-6, Calibre 2060-10, Calibre 2060-15, Calibre 2060-22, Calibre 2070-15, Calibre 2070-22, Calibre 2080-4, Calibre 2080-6, Calibre 2080-10, Calibre 2080-15, Calibre 9000-60, Calibre IM 400-11, Calibre IM 400-18, Calibre LG2010, Calibre LG2020, Calibre LG2023-10. See Polycarbonate... 

The equipment, which should be in accordance with ASTM D 1238, is first leveled. The temperature indicating device (previously calibrated as detailed in ASTM D 1238) is set to the requisite temperature (e.g. 300°C for a carbon fiber reinforced polycarbonate) and allowed to stabilize for 15 min. About 5 8 g of predried molding compound is weighed out and over a period of 1 min introduced into the cylinder with frequent tamping to expel air. The antiwobble piston (mass 100 g) is inserted and after 4 min, the test load (e.g. 5 kg for carbon fiber... 

Polycarbonate is available in blow molding, extrusion, and injection molding grades. Major suppliers include GE Plastics (Lexan), Bayer (Apec, Makrolon), Ashley Polymers (Ashiene), Mitusbishi Gas (lupilon), Dow Chemical (Calibre), Bay Resins, ComAlloy, DSM Engineering, LNP (Lubricomp), Nova Polymers, Federal Plastics, Ferro (Karlex), and Compound Technologies. 

The rest of the potential advantages included in the list above have been hardly ever applied to the field of polymer analysis so far. In fact, coupling of the ETV to an instrument equipped with a dynamic reaction cell has been reported only once, with the purpose of further removal of matrix-related interferences, allowing the use of isotope dilution for calibration [33]. Likewise, isotope ratio determination has been only reported for the direct analysis of particulate uranium from the nuclear industry embedded in polycarbonate films [35], while no references can be found for speciation analysis in polymers. This circumstance is probably due to the fact that there has not been a real need for this analytical information to be obtained, although there is no... 

The universal calibration method has proved valid for poly(dimethyl siloxane) and polycarbonates, and poly(styrene-c -divinyl benzene) in dimethylformamide. but only if the solvent contained lithium bromide in sufficiently high concentration. ... 

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