Thermomechanical testing

The thermomechanical tests of synthesized BSN showed, that the temperature magnitudes of glass transition and fluidity greatly depend on the composition and construction of the initial substances and are in in the interval 207-217 °C and 250-350 °C correspondingly. 

Thermomechanical tests and the physical state of hypercrosslinked networks... 

Mechanical and thermomechanical tests for adhesives are primarily used to evaluate the stress imparted by adhesives on bonded parts. Included in this category are... 

J. Vicens, F. Doreau and J. L. Chermant, Microstructural Characterisation of SiCfTMAS Composites in the As-Received State and After Thermomechanical Tests, Composites Part A 27A, 723-727 (19%). 

Similar thermomechanical tests were conducted for the CP-PSMP composites with 3% and 9% CP, as shown in Figures 6.18 and 6.19, respectively. From Figures 6.17 to 6.19, it is seen that as the CP content increases, the peak recovery stress (point E) and stabilized recovery stress (point F) decreases. This is understandable because the PSMP is stiffer than the CP at the glassy temperature, leading to a higher peak recovery stress with a higher PSMP content. The reason is that the peak recovery stress is basically an accumulation of thermal stress due to... 

Sauter, T., Heuchel, M., Kratz, K, and Lendlein, A. (2013) Quantifying the shape-memory effect of polymers by cyclic thermomechanical tests. Polym. 

Maximum deformation, parameter in cyclic, thermomechanical tests Free state deformation after cooling Volume fraction Critical volume fraction Volume resistivity Maximum stress 1,4-Butanediol Carbon black Carbon nanotube Dimethylformamide DMTA Dynamic mechanical analysis at varied temperatures DSC Differential scanning calorimetry / Frequency... 

High temperature, parameter in cyclic, thermomechanical tests Low temperature, parameter in cyclic, thermomechanical tests Melting temperature... 

Programming temperature, parameter in cyclic, thermomechanical tests... 

The SME of the network nanocomposite with 42 wt% POSS content was investigated. Here POSS crystallites were used to fix the temporary shape. The cyclic thermomechanical test started with heating the composite to 110°C. At this temperature, the sample was deformed by applying a load of 0.23 N and then cooled under this load to 30 C (POSS crystallization occurred according to DSC measurements... 

Fig. 15 Thermomechanical properties of SMPU/POSS nanocomposites, (a) Storage tensile modulus and tanS depending on temperature for SMPU with different POSS/polyol ratios (i) 0, (ii) 0.98, (iii) 1.67, and (iv) 2.63. (b) Cyclic thermomechanical tests for SMPU/POSS (POSS/polyol = 2.623). Three cycles are shown (solid line) first cycle, (broken line) second cycle, and (dotted line) third cycle. The asterisk marks the beginning of the cycle and the arrows denote the various stages, specifically (1) deformation, (2) cooling/fixing, (3) unloading, and (4) recovery. Reprinted with permission from [117], Copyright 2008, American Chemical Society...

Keywords Shape-memory effect Shape-memory polymer morphology Thermomechanical tests... 

Cyclic, Thermomechanical Testing of Triple-Shape Polymers. 130... 

Fig. 12 Scheme of a three-point flexural test, (a) Scheme of the shape-memory effect (SME) in polymers as defined by four critical temperatures. The value of 7 is a material property. Tiow is always less than Tg, whereas Tiugh may be above or below Tg, depending on the desired recovery response. (b) Schematic of the three-point flexure thermomechanical test setup. Taken from lef. [63], Copyright 2005. Reprinted with permission of John Wiley Sons, Inc. 

Impact of Temperature Dependent Test Parameters Applied in Thermomechanical Tests on Dual-Shape Properties... 

Besides the variation of the thermomechanical test set-up (e.g., cyclic, thermomechanical tests or three-point flexural bending tests) and the application of different types of programming and recovery modules as described in Table 2, the resulting... 

Fig. 14 Results of a strain-controlled cyclic, thermomechanical test. Results of strain-controlled cyclic, thermomechanical test of amorphous polymer network LGF2 synthesized from (ohgo[(l-lactide)-ran-glycolide]dimethaycrylates (M = 2,800gmop and Tg = 53 °C) for different Tiow (a) Tiow = 10°C and (b) Flow = 50°C n cycle number, a stress elongation. Taken and modified from ref. [13], Copyright 2007. Reproduced by permission of The Royal Society of Chemistry (RSC). http //dx.doi.oig/10.1039/b702515g...

Characterisation of SMPs by techniques such as cyclic thermomechanical tests and differential scanning calorimetry (DSC) is typically conducted in the dry state. Although such standard dry conditions are highly relevant to compare SMP properties with data from the literature, the impact of a physiological environment should generally be considered for SMP for biomedical applications. 

Loading the same drugs by swelling into amorphous SMP networks derived from star-shaped oLG tetrole did not affect the materials shape-memory functionality as can be seen from congruent curves in cyclic thermomechanic tests (Eig. 8a). 

These and other complementary thermomechanical tests have been carried out on injection-molded GFPPS components in order to set processing conditions and, thereby, maximize the plastic s mechanical stabihty. These GFPPS components are part of a telecommunication system s optoelectronic package (Bair and Osenbach 2004). 

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