TA Instruments DSC

DSC measurements were carried out with a TA Instruments DSC 2920 to determine the Tc of the polymer solutions. The DSC thermograms of the polymer solutions (50mg/l in deionised water) were recorded at a heating rate of 5 °C/min. The onset of the endothermic event was taken as Tc. 

Thermal analysis was conducted using TA Instruments DSC Q-100. The calibration was carried out using indium and sapphire standards. Heating and cooling rates of 10°C min were used over the studied temperature range. 

The DSC thermogram of ( )-methocarbamol is shown in Figure 7. The analysis was conducted on a TA Instruments DSC 2910, under a nitrogen atmosphere, at a scan rate of 10°C/min over the range of 50°C to 150°C. The melt onset temperature was found to be 94.06°C and the maximum temperature 98.06° C. The thermogram did not exhibit any exotherms or endotherms other than that associated with the melt. The estimate of the heat of fusion (AH) was 163.9 joules/gm. 

Mass spectra were recorded with the Esquire-LC 00084 and with MALDl-TOF MS Bruker Biflex IV. DSC and TGA measurements were carried out using a TA instruments DSC 2920. The DSC as well as the TGA measurements were performed at a sean rate of 5 K/min under nitrogen atmosphere. 

The phase transition temperature of the 5 wt% aqueous polymer solution was determined by DSC with a TA Instruments DSC 2920. The P2VP-block-P (NIPAAm-co-DMIAAm) block copolymer has a lower value of (Tcr=25 °C) than PNIPAAm (Tcr=33 °C) due to the additional hydrophobic P2VP and DMIAAm components whereas the PNIPAAm-DMAAm-DMIAAm terpolymer has a higher value of T r (Ter=43 °C) than PNIPAAm due to the additional hydrophilic DM A Am component (Table 2). 

Injection moulded polypropylene-PIB-silica samples were studied using TA Instruments DSC 2920. The samples were heated and cooled twice from 0°C to +210°C with scan rate 10°C/min. 

X-ray diffraction was performed at room temperature to evaluate the dispersion of the silicate layers in the PCL matrix. The thermal properties of the samples were then analysed by using a TA Instrument DSC 2910. Dynamic and isothermal crystallization analysis were performed on samples kept at 80 °C for 5 minutes to eliminate the previous thermal history and to allow for complete melting of the crystalline phase. 

Samples of PMMA were heated in a vacuum oven at 120°C for 24 hours to drive off any moisture that had been absorbed. One sample of approximately 15 mg was placed in aluminum pans in a TA Instruments DSC 2920. The sample was equilibrated at 25°C and then heated from 25°C to 180°C at 10°C/min for the first run. The sample was then cooled slowly, again equilibrated at 25°C and the heating process was repeated for a second run. All of these tests used nitrogen as a purge gas. The glass transition function in TA Instrumental Analysis was used to calculate the Tg of the material by finding the inflection point in the Tg step. 

Measurement of Crystallinity Fiber crystallinity of the calibration samples was measured using a TA instruments DSC Q 1000. Typically 3-7 mg of the fiber sample was heated at 10°C/min. The heat of fusion from the first heat was used to calculate the propylene crystallinity. A value of 165 J/g was used for the heat of fusion corresponding to a perfect polypropylene crystal. 

A TA Instruments DSC 2920 (TA Instruments, New Castle, Delaware) was used to study the thermal properties and crystallinity of the microgels. Microgels with excess squalane were sealed in an aluminum hermetic pan and cooled to 0 °C in the DSC cell before being heated at a rate of 10 °C/min to 155 °C. Following this, the sample was brought back to -40 °C with a cooling rate of 10 °C/min and this process was repeated for an additional seven cycles. 

S.M. Marcus and R.L. Baine, Estimation of bias in the oxidative induction time measurement by pressure DSC, Application note TA-228, TA Instruments, Inc., New Castle, DE, USA. 

Measurements of differential scanning calorimetry (DSC) were obtained on a TA Instruments 2910 thermal analysis system (Fig. 2). Samples of approximately 1-2 mg were accurately weighed into an aluminum DSC pan, and covered with an aluminum lid that was crimped in place. The samples were then heated over the range of 20-140 °C, at a heating rate of 10 °C/min. Valproic acid was found to boil at 227 °C. 

Thermal decomposition was performed using a SDT Q-600 simultaneous DSC-TGA instrument (TA Instruments). The samples (mass app. 10 mg) were heated in a standard alumina 90 il sample pan. All experiments were carried out under air with a flow rate of 0.1 dm3/min. Non-isothermal measurements were conducted at heating rates of 3, 6, 9, 12, and 16 K/min. Five experiments were done at each heating rate. 

Fig. 1.26. Instrument DSC 2920 with DTA-measuring cell. This installation is not designed for low temperatures, but can be modified for this purpose. (Commercial standard installations for low temperatures have not been found by the author.) (Schema and photograph TA Instruments, Inc. New Castle DE 19720, USA.)...

The purpose of differential thermal systems is to record the difference in the enthalpy changes that occurs between the reference and the test sample when both are heated in an identical fashion. Several publications are available concerning the theoretical aspects and applications of various thermal analysis techniques, including the DSC [71-74]. Commercial instruments are available from a number of companies including Perkin-Elmer, TA Instruments, Toledo-Mettler, SET ARAM, Seiko, and Polymer Laboratories. 

A differential scanning calorimeter (DSC), Dupont Instrument, Model DSC2910, was used to determine the glass transition temperatures. Thermo-gravimetric analyses were carried on a thermogravimetric analyzer (TGA), TA Instruments, Model Hi-Res TGA 2950. 

The compositions of the composites were determined simply by weighing the tared solid sample. Melting endotherms and glass transition temperatures were determined using a TA Instruments 2910 modulated differential scanning calorimeter (DSC) operated with a 3°C/min ramp rate, a 0.75 °C oscillation amplitude, and a 60-s oscillation period. 

Fig. 1.45.1. Artist s view of a DSC cell in Tzero technology as used in modulated DSC (MDSC) processes. 1, Sample and reference table made from one piece of constantan 2, chromel thermocouples directly connected to the constantan tables 3, Tzero sensor from chromel-constantan in the middle between sample and reference table (TA Instruments, New Castle, DE, USA...

Fig. 1.46. Modulated DSC apparatus, Model Q 1000, using the details of Figs.l. 45.1 and 1.45.2 (TA Instruments, Newcastle, DE, USA)...

The thermal behavior of pantoprazole sodium was examined by DSC, using a TA Instrument model 91 OS differential scanning calorimeter calibrated with indium. Pantoprazole sodium samples ranging from 5 to 10 mg were run at a heating rate of 5°C/min over a temperature range of 50°C to 179°C. 

Figure 4 Differential scanning calorimetry endotherms (DSC model 2910, TA Instruments, New Castle, DE) of cowpea protein-corn starch blends in different ratios (R) at pH 7 and scanning rate 5°C min-1. (Courtesy of Okechukwu and Rao, 1996b.)...

The TA Instruments heat-flux DSC design (Figure 3.23c and Figure 3.5), where the sample and reference rest on elevated platforms of a constantan disk, also has minimal baseline float since the high thermal conductivity of the disk has an effect similar to that of the nickel block. The latter device is generally more calorimetric than the nickel block design. By mea-... 

---