Polyolefins polymers

The additive analysis reported has been largely confined to conventional polymers (polyolefins, polycondensates, PS, PVC, etc.) Very little work, if any, has been reported on advanced engineering plastics. Similarly, also relatively little research activity has focused on additives in acrylics or blends. 

Recall that in the process of low-pressure moulding, thermoplastic polymers (polyolefins, polyamides, or their compositions) are loaded into a cylinder of the adiabatic extruder, plasticized and injected into a mould at low pressure. The formed article is cooled in the mould and removed due to shrinkage phenomena. 

Synthetic polymers polyolefines (polystyrene, polystyrenedivinylben-zene), acrylic polymers (polyacrylate, polyacrylamide, polymethacrylate, etc.) and others such as polyvinyl alcohols, polyvinyl chloride, polyte-trafluoroethylene, polyamides, polyurethane, silicone, etc. 

Although solution blending has only been used at the lab scale at this time, compared with the in situ process, it may be more industrially friendly, particularly for the primary polymer producers who have operations, which can easily recover and recycle the solvent. High dilution is required and this may have an effect on the production of the PNs and the process is quite dependent on the individual polymer. Some polymers have many solvents from which to choose while others do not. A typical example is polystyrene, which can dissolve in a variety of solvents, so it is easy to find a solvent that is compatible with both the clay and the polymer. Polyolefins, on the other hand, require high boiling solvents and the high temperature may exert an effect of thermal degradation on the modifier. 

Scientific and technological progress, like other areas of human endeavor advances by a cyclical process of gradual evolution interspersed -with occasions of scientific revolution (Mark 1987). For example, let s consider Figure 10-1, which illustrates the development of polymer science through the commercialization of one family of polymers, polyolefins (Sinclair 2001). One could construct a similar plot for other families of polymers. Revolutionary episodes... 

The melt (flow) index has become a widely recognised criterion in the appraisal of extrudability of thermoplastic materials, especially polyolefins. It is standardised as the weight of polymer (polyolefin) extruded in 10 min at a constant temperature (190 °C) through a tubular die of specified diameter (0.0825 in. = 2.2 mm) when a standard weight (2.160 kg) is placed on the driving piston (ASTM D 1238). 

Most commonly used separator materials for alkaline Zn/Mn02 batteries are nonwoven polymers, such as cellulose, vinyl polymers, polyolefin, and others. The separator materials must be chemically stable in concentrated KOH solutions and electrochemically stable under both oxidizing and reducing conditions in the cell. In addition to its good electronic insulation, physical strength, and porous structure, good wettability to concentrated KOH solutions is especially crucial to provide a good ionic pathway for the battery operation. 

Polymers polyolefins, vinyls, polystyrene, polyester, melamine, and terephthalic acid... 

Secondary aromatic amines are effective antioxidants in the protection of saturated hydrocarbon polymers (polyolefins) against autooxidation. Their role in the stabilization of unsaturated hydrocarbon polymers (rubbers) is more complex depending on their structure, they impart protection against autooxidation, metal catalyzed oxidation, flex-cracking, and ozonation. The understanding of antioxidant, antiflex-cracking and antiozonant processes together with involved mechanistic relations are of both scientific and economic interest. 

The effect of ozone on saturated polymers, polyolefins (PO) and polystyrene (PS) in particular, is underrated. Ozone is involved in the initiation phase of their oxidation. Its attack results in formation of R, RO, ROO, ROOH and I CO species in PO, and free radicals and polymeric peroxides in PS. Moreover, ozone decomposes hydroperoxides into oxygen-centred radicals RO, ROO and HO. ... 

Ccramer . [Pemdite/Polymers] Polyolefin wax adducts ertmlsifiaUe waxes... 

The syntheses, properties and potential applications of polyolefin/non-polyolefin hybrid polymers, Polyolefin Hybrids , via controlled/living radical polymerization have herein been introduced. Polyolefin Hybrids can control the phase stractures, and the surface stmctures on molded polyolefin materials. Polyolefin Hybrids can enhance the physical properties of polyolefins as well as add new properties such as hydrophilicity and antibacterial properties to them. Novel value-added polyolefin materials, Polyolefin Hybrids , have great potential as new value-added materials. 

Heparinized polymers Polyolefin-based systems Hydrogels Other polymers... 

Polyolefins are synthetic polymers of olefinic monomers. They are the largest polymer family by volume of production and consumption. Several million metric tons of polyolefins are produced and consumed worldwide each year, and as such they are regarded as commodity polymers. Polyolefins have enjoyed great success due to many application opportunities, relatively low cost, and wide range of properties. Polyolefins are recyclable and significant improvement in properties is available via blending and composite technologies. 

Hydrophobic polymers (polyolefins, polystyrene, polyethylene terephtha-late, pentaplast, fluoroplasts) contain small amounts of polar groups in their macromolecular composition able to interact with water and electrolytes. To that extent, the permeability mechanism of electrol3des in hydrophobic polymers is similar to that of gases. 

The main progress in the science of ageing and stabilisation of polymers has generally been related to large tonnage carbochain polymers polyolefins, polyfvinyl chloride), rubbers, acrylic polymers. This is a consequence of not only their interest to industry, but also of the existence of fundamental investigations of cracking and oxidation of individual aliphatic compounds. 

Polyacryl- amide All uncross-linked polymers Polyolefins Polyacrylo- nitrile Polyamides Polyfluoro hydro- carbons... 

Chem. Descrip. y-Methacryloxypropyltrimethoxysilane CAS 2530-85-0 EINECS/ELINCS 219-785-8 Uses Adhesion promoter for adhesives and coatings coupling agent for glass-reinforced and min.-filled thermosetting resins blend additive in resin systems (polyester, acrylic), and filled or reinforced thermoplastic polymers (polyolefins, polyurethanes)... 

In the last years, the selection of polymers had been extended to most of the commonly used membrane materials cellulose acetate [25], polyamide [34,36], polyacrylonitrile [37], polysulfone [26,37], and modified polysulfone [23], but also including polystyrene and PVC [37], or PVC-co-PAA [38]. The exceptions are the hydrophobic—and almost nonfunctional— polymers (polyolefines, PVDF, or Teflon). However, because both recognition sites and pore structure are fixed at the same time within the same material, a comparison of the efficiency of different MIP membranes, and thus polymer materials, was rather complicated [26]. 

Hindered amine stabilizers (HAS) are the most common class of the curative additives and their application is the state-of-the-art in photoprotection of carbon-chain polymers, polyolefins in particular. HAS shape future polymer development, promote their consumption in new areas and expand material performance by increasing its lifetime. Application of HAS is based on a long-term effective development and is connected with commercial benefits for polymers. An optimized technical application of HAS required explanation of their chemistry and activity mechanisms in different phases of the oxidative degradation of polyolefins [14-17]. 

Uses Light stabilizer, free radical scavenger, antioxidant for polymers, polyolefins, food-grade polymers... 

Aliphatic or side-chain aromatic hydrocarbon polymers (polyolefins and polystyrene) give no char while the CR percentage of main-chain aromatic, condensed aromatic, heterocyclic (high-temperature) polymers may be as high as 70%. Halogen-containing polymers are outside the scope of the above relation. 

Sodium etch Sodium hydroxide Sanitizing melamine or urea polymer, polyolefin, polyethylene oxide, polystyrene, polysulfone, and styrene-acrylonitrile (SAN) Fluoroplastics and some polyesters Polystyrene, polyesters, polyamide, and polysulfone Homopolymer polyacetal Developed by... 

Recommended for polymers polyolefins and cold-cured polyester resin ... 

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