DMA characterization

The DMA characterization was made of the series of polymers denoted PU 1 to PU 5 as listed in Table 3.11. The samples were tested in the tensile mode with a starting distance between the clamps of 45 mm. The cooling conditions were room temperature till -60°C cooling rate of 10 K/minute, -60°C to -120°C 3.5 K/min and -120°C to -140°C 2 K/min. The test started at -140°C and the complex modulus , storage modulus loss modulus E" and the loss factor were measured as function of temperature at a heating rate of 1 K/min. The instrument was operated with controlled sinusoidal force with a frequency of 1 s ... 

DMA CHARACTERIZATION OF CROSSLINKED POLYMERS Polyester with 30% glass... 

A number of analytical techniques such as FTIR spectroscopy,65-66 13C NMR,67,68 solid-state 13 C NMR,69 GPC or size exclusion chromatography (SEC),67-72 HPLC,73 mass spectrometric analysis,74 differential scanning calorimetry (DSC),67 75 76 and dynamic mechanical analysis (DMA)77 78 have been utilized to characterize resole syntheses and crosslinking reactions. Packed-column supercritical fluid chromatography with a negative-ion atmospheric pressure chemical ionization mass spectrometric detector has also been used to separate and characterize resoles resins.79 This section provides some examples of how these techniques are used in practical applications. 

Structural characterization of the surface metal oxide species was obtained by laser Raman spectroscopy under ambient and dehydrated conditions. The laser Raman spectroscope consists of a Spectra Physics Ar" " laser producing 1-100 mW of power measured at the sample. The scattered radiation was focused into a Spex Triplemate spectrometer coupled to a Princeton Applied Research DMA III optical multichannel analyzer. About 100-200 mg of... 

Two separate analyses of a sample, utilizing two eluent buffer systems of different ionic strength, are required for the complete characterization of a sample because As(lll), if present in the sample, will interfere with the resolution and determination of DMA. The two eluent buffers which are used are Eluent 1 - 0.0024 M NaHC03/0.0019 M Na2C03/0.001 M NapB Oj and Eluent 2 - 0.005 M... 

Poly(", -ethyl L-glutamate) (0.10 g), prepared by the polymerization of the corresponding NCA, was allowed to swell in DMA (0.8 mL) and ferrocenylmethylamine 104 (0.2 g) was added. The viscous orange soln was heated to 75 °C for 18 h, then cooled, and diluted with EtOH (5mL) and Et20 (20 mL). The ferrocene-modified polypeptide 105 (0.10 g) formed a dark orange solid characterized by elemental analysis, which gave 6.0% of iron IR (KBr) vCq 1725, 1640,1530 cm-1. 

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