LDPE, additives Lubricants

Hinman et al. [492] have compared SFE and ASE in the extraction of antioxidants from LDPE. Comparable extraction yields were obtained with both techniques. However, sample clean-up was necessary after ASE , while with SFE the extract could be analysed directly without any post-extraction clean-up. Supercritical fluid extraction of 15 polymer additives (AOs, UVAs, process lubricants, flame retardants and antistatic agents) from eight PS formulations was compared to dissolu-tion/precipitation extractions [557], Additive recoveries were comparable. Numerous additional comparisons can be found under the specific headings of the extraction techniques (Sections 3.3 and 3.4). 

LDPE and PTFE are manufactured by processes involving little contact with metals, and should not be a major source of aluminum. On the other hand, HDPE and PP have similar manufacturing processes, based on catalysis, that involve aluminum, among other metals. The contamination risk may therefore be very high. In addition, the manufacture of the container itself can lead to aluminum contamination, considering the use of lubricants, stabilizers and other additives. For example, metal soaps, such as aluminum, magnesium, sodium, and tin, were sanctioned by the FDA to be used as stabilizers in plastic containers for parenteral nutrition solutions [76]. 

Additionally, these authors also found that the presence of lube oil decreased the activity of the catalysts due to the presence of both sulphur- and nitrogen-containing compounds (4000 ppm of sulphur and 85 ppm of nitrogen) that poisoned the acid sites. Consequently, higher temperatures (450-500°C) should be employed to obtain complete conversion in the catalytic cracking of the LDPE-lubricating oil mixture over Al-MCM-41 and nanocrystalline HZSM-5 catalysts. 

Lubricants may be added either as an additive or at the fabrication stage as a processing aid. In general lubricants prevent adhesion with metal parts. Lubricants may be solids, such as waxes, stearates, i.e. fatty acid esters, fatty acid amides, or liquids such as liquid paraffins. Lubricants may also improve the flow and thereby lower the temperature of the moulding operation. For example, a silicone additive polydimethyl siloxane may be used in LDPE and HOPE films to improve flow. Stearamides are also used. 

U.S. Pat. No. 6,632,863 [115] (by Crane Plastics Company, Timber-Tech) discloses a wood-plastic composition manufactured as feedstock pellets comprising 55-90% cellulosic material such as wood flour and wood fiber, 10-40% of polyolefin such as HDPE, LDPE, and polypropylene, and 0-35% total of additive(s), such as lubricants and inorganic fillers, such as talc and mica. 

EINECS 246-614-4 Isooctyl phosphite ((C8H170)3P) Phosphorous acid, triisooctyl ester Triisooctyl phosphite Weston TIOP. Intermediate insecticides lubricant additive specialty solvents stabilizer for acrylics, nylon, unsaturated polyester, PVC improves antiwear and antifriction properties. Stabilizer tor hot-melt adhesives. PU, polyesters used in molding, extrusion, and film applications in PP, HOPE, LDPE, PVC, and polyesters also useful for PP fiber applications and calendering of PVC. Oil d = 0.891. Albright i Wilson Americas Inc. GE Specialities Stave. 

Slip, antislip, and antiblock agents [30, 31] do not facilitate molding or semifinished product manufacture as do lubricants. What they do is to simplify further processing - of foils in particular. Foil bags that have been stored in stacks cannot be readily picked up or opened, problems that are particularly noted with LDPE and PP. An effective slip agent with LDPE is addition of 0.05 % oleic acid amide and with PP the same amount of eruca acid amide. Additive manufacturers supply concentrates of these compounds in granulate form for addition to molding compounds [50]. 

Chem. Descrip. LDPE homopolymer CAS 9002-88-4 EINECS/ELINCS 200-815-3 Uses Additive for printing inks flatting agent, antisettling agent in paints dispersant, color enhancer in color cones. in floor polishes lubricant for plastics processing... 

After cutting, grinding and after a first separation of the metals, the plastics are sent. Fig. 13a, to a floating section for separating PVC and PE. After a passage in an electrostatic separator to eliminate the last particles of metals. Fig. 13b, PVC is blended with additives (stabilizers, lubricants, colorants), compounded and extruded in a twin screw extruder. The recycling of LDPE insulators from cables is subjected to a similar processing. 

Figure 2.16 shows the TG separation of an LDPE formulation containing a lubricant, carbon-black and inert filler using an optimised stepwise analysis mode. The percentage lubricant, polymer, carbon, and inert filler can quantitatively be determined [272]. Lever et al. [273] have shown that HRTGA gives a much cleaner resolution of mass losses than conventional TG of a polymeric derivative used as an oil additive. Also the high resolution TG analysis of DOP in vinyl plastics has been reported [229]. 

The resistance to abrasion is closely related to other factors such as hardness, resiliency, and the type and amount of added fillers and additives. The resistance to abrasion depends on factors such as test conditions, type of abrading material, and development and dissipation of heat during the test cycle. It is most often measured by the weight loss when a material is abraded with an abrader after a number of revolutions (at least 5000). The Taber abrader is widely used. Eor softer materials, less abrasive wheels with a smaller load on the wheels may be used. Wear may be high when reinforced parts are in contact with unreinforced parts. Use of lubricated reinforced grades may reduce wear when in contact with an unreinforced component. The abrasion resistance of LDPE... 

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