![]() In addition, the curing of monomers can be used to obtain patterns, if only parts of the surface are crosslinked, whereas the uncrosslinked areas remain soluble. In order to allow a solvent-based step-by-step preparation, solidification by crosslinking has great advantages. For most appliances multilayer structures are needed. On the other hand, this approach has several advantages for the device preparation with conductive LCs. 28 Here care must be taken that the orientation is not lost during the polymerization. The second approach is to use LC monomers that are aligned first and polymerized in the oriented state. However, this reduced mobility makes the alignment of the polymers difficult. They have a high viscosity that stabilizes an orientation. To circumvent this problem two approaches are possible. ![]() ![]() But low molar mass LCs (1) tend to reorient – depending on the phase – in electric fields (see Section 8.06.3) and most importantly (2) lack the mechanical stability of polymers. Brehmer, in Polymer Science: A Comprehensive Reference, 2012 8.06.2.1 Crosslinkable Liquid Crystalsįrom the results with low molar mass LCs, it is obvious that the charge carrier mobility profits from the higher order in this mesophase. Polymers for Advanced Functional Materials Hence from Figure 2.28 the compressibility factor is about 0.835. If gas conditions of 100 bar(a) and 400 K are assumed, the reduced pressure and temperature are 2.2 and 1.56 respectively The pseudo mean critical temperature for the gas mixture is 255.33 K –Īssuming gas conditions of 10 bar(a) and 300 K, the reduced pressure and temperature for the mixture are 0.22 and 1.17 respectively –įrom the psychometric chart ( Figure 2.32) the compressibility factor for the gas mixture is approximately 0.95 – The pseudo mean critical pressure for the gas mixture is 45.53 bara – However for most initial calculations this value may be used. NOTE: The value of the isentropic exponent will vary a little with temperature and pressure. Notice there are two different sets of diagonal lines one for wet bulb temperature and one for specific volume. The ‘state point’ can be found at the intersection of the vertical dry bulb temperature line and the percentage saturation curve. Most users will probably know the dry bulb temperature and the relative humidity. The two parameters can be considered as interchangeable for industrial purposes. Percentage saturation is also known, incorrectly. The “real” air properties specific volume, specific enthalpy, percentage saturation and moisture content can be read from the chart. Read moreĪn ordinate is drawn vertically from the dry bulb temperature to the point of intersection with the relevant diagonal wet bulb temperature line. Designers are encouraged to get updated mechanical property data on the grade being used. Since this work was reported, resin manufacturers have made improvements in HDPE materials and new grades of HDPE have been developed that have improved modulus values. The authors conclude that HDPE is suitable for use up to at least 40☌ (104☏) in hydrocarbons, and possibly up to 60☌ (140☏) in well-controlled, fully understood applications. ![]() This is consistent with known properties of HDPE exposed to liquid hydrocarbons. The authors reported that the maximum swell was about 6% and the maximum weight gain was about 10%. It is clear from these measurements that there are useful properties at 60☌ (140☏) for this particular HDPE grade. 3.1.1 Molar mass (M) and ideal gas specific heat capacity For problems such as the simultaneous process and working fluid design of Organic Rankine Cycles, however, these transport properties act strongly on the objective function ( Lampe et al., 2012). Transport properties do not enter the case study presented below and the inclusion of transport properties into the CoMT-CAMD methodology is therefore not detailed here. We use Quantitative Structure Property Relationship (QSPR) methods for this purpose.Ĭorrelating transport properties, such as shear viscosity, is subject of our current development with very satisfying results. Since the CoMT-step optimizes a hypothetical molecule entirely characterized by solvent parameters of the PC-SAFT model, it is necessary to estimate these properties based on the solvent parameters. ![]() Examples are the molar mass, the ideal gas heat capacity or transport properties. To allow for a full process optimization within the proposed CoMT-CAMD method, physical properties beyond the standard properties accessible from the PC-SAFT model are required. Joachim Gross, in Computer Aided Chemical Engineering, 2014 3.1 Correlation of physical properties using QSPR 24th European Symposium on Computer Aided Process Engineering ![]()
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