Molecular weight, influence pressure

The differences cannot be easily explained. The selection rules are often heavily influenced by economical considerations alone. The technological parameters are flux, recirculation rate, chemical compatibility, pore size or molecular weight cutoffs, pressure and temperature limitations, and cleane-ability. Once the feasibility has been established, the engineering design and scale-up come into play. 

Plastic material viscosity is influenced by four main factors shear rate, temperature, molecular weight, and pressure [23-25]. 

Polymer-Fluid Equilibria and the Glass Transition Most polymer systems fall in the Class HI or Class V phase diagrams, and the same system can often change from one class into the other as the polymer s molecular weight changes. Most polymers are insoluble in CO9 below 100°C, yet CO9 can be quite sohible in the polymer. For example, the sorption of CO9 into silicone rubber is highly dependent upon temperature and pressure, since these properties have a large influence on the density and activity of CO9. 

Molecular weight, temperature, and pressure have little effect on elasticity the main controlling factor is MWD. Practical elasticity phenomena often exhibit little concern for the actual values of the modulus and viscosity. Although MW and temperature influence the modulus only slightly, these parameters have a great effect on viscosity and thus can alter the balance of a process. 

The molecular weight and density of the solvent influence the volume of the evaporated sample and hence the pressure wave. Solvent volatility nay Influence the distribution of sample between the vapor and droplet phases. The same sample amount dissolved in different solvents may produce different peak areas. 

It must be also considered that the reaction rates of different thermal processes which can occur simultaneously are influenced by the treatment conditions (temperature, heating rate, pressure, static or dynamic atmosphere). This will affect the relative quantities of the products formed and in some cases also their nature, when recombination reactions give rise to secondary degradation products. On account of its sensitivity and resolution power Py-GC/MS will also provide useful information on minor components present in a material, including low molecular weight additives and pigments. 

Pressure Dependence of the Segmental Relaxation of Polybutadiene and Polyisobutylene and Influence of Molecular Weight. 

The basic properties of mPE, such as the average molecular weight, molecular-weight distribution, or density depend mainly on the structure of the metallocene catalyst and its concentration in the polymerization reactor. They also depend strongly on the polymerization temperature and can be varied by incorporation of co-monomers. The influence of the pressure is only small. 

Figure 9.5-9. Influence of temperature on the number-average molecular weight. Pressure, 150 MPa Zr in feed, 0.012 mol ppm Al/Zr, 5,000 mol/mol n-hexane in feed, 10 mol.%.

A reciprocating compressor is a direct volume-reduction machine. The gas is simply squeezed out of a cylinder by a piston and pushed into the discharge line. The molecular weight of the gas does not influence the suction or discharge pressure of the compressor. The gas density does not influence the compressor performance or the work required by the driver. 

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