Polymer studies anvil

The torque-time curve was initially somewhat irregular due to the lateral extrusion of some of the sample material during the first few cycles of anvil oscillation. Data was taken after the torque-time curve had stabilized and approximated a square wave. A typical tracing obtained on PP is shown in Fig. 1. Note that during the experiment the rotation speed was increased about 5 fold with no apparent residual effect on the sample. There was only a small increase in torque associated with the higher strain-rate or sliding speed. This is typical of what has been observed with other polymers studied . 

The FTIR microscope is particularly useful for polymer studies because it is relatively easy to obtain a minute polymer specimen, by using a razor blade or a knife, that is thin enough to analyze by transmission. The specimen can be placed in a KBr pellet die or a diamond anvil and pressed to a thickness suitable for analysis. 

Ambient temperature emission intensities and lifetimes from the salts of Ru(bpy>3 + and of Ru(bpy)2(py)2 + as solids and as solutions in the polymers poly(4-vinylpyridine) (PVP) and poly(acrylic acid) (PAA) have recently been studied as a function of pressure to 7 GPa in a diamond anvil cell [33], For the Ru(bpy)3+ emission in the PAA and PVP solutions, intensities and lifetimes both decreased monotonically to about 35 and 50% of the original values, respectively, as pressure was raised from 0.1 MPa to 7 GPa. This... 

Another important area of polymer modification with subcritical and supercritical water is the hydrolysis of polycondensation polymers such as polyethylene terephthalate (PET), polyurethanes, and nylons for conversion to their monomers [ 37]. Specifically, in supercritical water, 91 % monomer recovery (terephthalic acid) is achieved at 400 °C and 400 bar in less than 15min reaction times [38]. Studies of these reactions using a hydrothermal diamond anvil cell to follow the phase changes during the reaction of PET... 

Evaporating solid polymeric particles (accompanied by considerable pyrolysis) and codepositing the volatile products (mostly radicals) with the metal vapor are used less often. This technique is employed for the formation of 10-mn-diameter copper islets in a polyethylene matrix. The explosive evaporation of a metal wire coated with a polymer and pulsed mechanochemical interactions (of the Bridgeman anvil type), etc. are the modifications of this method. Recently, interest has been shown in the ionic spraying of metals onto polymeric surfaces. Studies of the vacuum deposition of Au and Zn on PE and PTFE should be noted. " ... 

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