Process polymer industry applications

The presence of water as a reaction product from the pyrolytic processes or as adsorbed water on the material to be pyrolysed is not unusual. However, in analytical pyrolysis, water is not commonly added to the sample. During some pyrolytic processes with industrial applications such as wood pyrolysis, water is sometimes added intentionally. The main effect of water during pyrolysis is hydrolysis. This takes place as the temperature elevates. For polymers like cellulose or starch, the chain scission by hydrolysis (instead of transglycosidation) is the main effect of water addition. This can be seen in the modification of the yields of different final pyrolysis products. Therefore, the reproducibility in analytical pyrolysis may be influenced by the variability of water content of the initial sample [9]. 

For many industrial applications of plastics that are dependent on adhesive bonding, cold gas plasma surface treatment has rapidly become the preferred industrial process. Plasma surface treatment, which is conducted in a vacuum environment, affords an opportunity to minimize or eliminate the barriers to adhesion through three distinct effects (1) removal of surface contaminants and weakly bound polymer layers, (2) enhancement of wettability through incorporation of functional or polar groups that facilitate spontaneous spreading of the adhesive or matrix resin, and (3) formation of functional groups on the surface that permit covalent bonding between the substrate and the adhesive or matrix resin. Since plasma treatment is a process of surface modification, the bulk properties of the material are retained. The nature of the process also allows precise control of the process parameters and ensures repeatability of the process in industrial applications. Finally, several studies have demonstrated that these surface modifications can be achieved with minimum impact on the environment. 

The thermal stability of polymer nanocomposites plays a critical role in determining then-processing and industrial application, because it affects the final properties of polymer nanocomposites such as the upper-limit working temperature and dimensional stability for targeted applications. The TGA thermograms of the PEN/CNT nanocomposites with the CNT content are shown in Figure 4. The incorporation of the CNT into the PEN matrix increased the thermal decomposition temperatures and residual yields of the PEN/CNT nanocomposites... 

Core-and-shell composite particles based on inorganic cores with a polymer shell have also been investigated by several researchers, but do not seem to have reached industrial products. The reason for this is probably the high cost and possibly limited benefits of this type of latexes compared to existing products. A similar type of product is composite particles based on pre-emulsified polymers such as epoxies or polyesters (alkyds) with a subsequent addition of new monomers and polymerisation. This technique is partly connected to the process of miniemulsion polymerisation described in Section 1.2.2. A type of core-and-shell particles or at least multiphase particles may be obtained in this type of process. However, industrial applications of this type of products are not found on a large scale yet. Applications of polymer particles, mainly made by emulsion polymerisation, in the biomedical field was concentrated initially in the areas of blood flow determination and in vitro immunoassays. Microspheres have been employed for the determination of myocardial, cerebral and other blood flow and perfusion rates. Polymer particles and lattices, in particular, have been extensively used in immunoassays, starting in 1956, with the development... 

Thermal stability of polymer nanocomposites is one of the most important factors for polymer processing and industrial application of polymers [14]. TGA resifits of TLCP/MWCNT nanocomposites as a function of... 

Another example in the polymers industry is illustrated in Figure 17, which is a process aimed at the batch drying of waste residue with solvent recovery. In this application liquid or viscous waste solutions are pumped into a batch dryer where they are dried under vacuum to a solid granular residue. Vaporized water and solvent are recovered by condensation and then separated by gravity. The process scheme is flexible, offering a range of temperatures and vacuum levels for treating... 

Metallic polymers which are stable, soluble and processible, and therefore suitable for industrial applications ... 

Step-growth polymer industry, 2 Step-growth polymerization processes, design of, 13 Step-growth polymers applications for, 2 histoiy of, 1 -2... 

Details are given of the development of energy and material recycling processes for thermosetting polymer composites. Applications in the cement industry and in coal fired fluidised bed combustion plants are discussed. 3 refs. 

Campion, R.P., Permeation through Polymers for Process Industry Applications, MTI Publication No. 53, Materials Technology Institute of the Chemical Process Industries, St Louis, MO distributed by Elsevier Science, Amsterdam, The Netherlands, 2000. 

SPME-IR has been applied to VOCs in soil samples [547], Industrial applications to in-process streams can well be envisaged. SPME has not yet extensively been explored for polymers, but the determination of residual volatiles, semi-volatiles and degradation products in polymers has been reported [548]. It is equally well possible to use SPME for plasticiser analysis in various matrices (water, milk, blood, processed food, etc.). 

In an industrial application dissolution/reprecipitation technology is used to separate and recover nylon from carpet waste [636]. Carpets are generally composed of three primary polymer components, namely polypropylene (backing), SBR latex (binding) and nylon (face fibres), and calcium carbonate filler. The process involves selective dissolution of nylon (typically constituting more than 50wt% of carpet polymer mass) with an 88 wt % liquid formic acid solution and recovery of nylon powder with scCC>2 antisolvent precipitation at high pressure. Papaspyrides and Kartalis [637] used dimethylsulfoxide as a solvent for PA6 and formic acid for PA6.6, and methylethylketone as the nonsolvent for both polymers. 

UV-radiation curing has become a well-accepted technology which has found numerous industrial applications because of its distinct advantages 1-3. One of its main characteristics is the rapidity of the process which transforms quasi-instantly the liquid resin into a solid polymer under intense illumination by a UV-source or a laser beam4. The polymerization rate can be finely controlled by acting on the initiation rate through the intensity of the UV radiation. It is... 

---