Polyolefins/polyamide

Blends based on polyolefins have been compatibilized by reactive extrusion where functionalized polyolefins are used to form copolymers that bridge the phases. Maleic anhydride modified polyolefins and acrylic acid modified polyolefins are the commonly used modified polymers used as the compatibilizer in polyolefin-polyamide systems. The chemical reaction involved in the formation of block copolymers by the reaction of the amine end group on nylon and anhydride groups or carboxylic groups on modified polyolefins is shown in Scheme 1. 

Films of polyolefins, polyamides and poly(vinylidene dichloride) are made using this technique. As most of the films are used for flexible packaging, further down-stream surface treatments are usually applied to improve performance. For example, aqueous polymer emulsions, e.g., poly(vinylidene dichloride), or delaminated clay particles improve the barrier properties as will metallising with aluminium vapour. Corona discharge, causing slight surface oxidation, improves printability. 

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. 

It is worthwhile to note that chemistry plays a major role in the morphology and control of mechanical properties in complex systems like PPE blends with crystalline polymers, such as polyolefins, polyamides (PA) and polyesters (18). The amount of copolymer formed during the reactive extrusion between functionalised PPE and PA has a significant effect on the impact-strength of blends. The latter levels off only above 10% of copolymer. 

Keywords Block copolymers, Interface reactive injection moulding, Polyamide degradation, Polyolefine polyamide graft copolymers, PTFE polyamide materials... 

Among the earliest uses of MIR transmission and ATR spectroscopy has been the study of the oxidation of polymers. The principal oxidation products from polyolefins, polyamides and elastomers such as EPDM are carbonyl-containing species including aldehydes, ketones, esters, lactones, acids and peracids. The reaction scheme for their formation has been determined from studies of model compounds and polymers over the past 20 years, and a typical scheme is shown in Scheme 3.1 (Blakey, 2001). 

Further developments are still being made in membrane materials and membrane modules. There are reports, in particular, of hydrophobic membranes made of polyolefins, crosslinked polyolefins, polyamides, polyaramids, poly(vinylidene fluoride), PTFE, polyimides, and suchlike. 

Polyolefin Polyamide Polyester Urethane Nylon 6 Nylon 66... 

In the field of gas separation a large number of materials can be used (polyolefins, polyamides (polvaramids), polyesters, polysulfones and. more specifically, polyvinyl-... 

Polyolefin-polyamide melt blends are striking in not only the lack of miscibility, but also the large interfacial tensions between the two melt phases. Investigations of these phenomena in our laboratories (118,124-126) have made numerous studies of these polymer blend systems and found that their phase morphology are quite unstable and trend to coalesce especially under quiescent or low deformation rate conditions. Similar to polyolefin-polystyrene blends, they also show weak interfacial adhesion (118,124,127) (as shown in Fig. 2.9). The mechanical properties of the... 

Polymers used in inhibited plastics (polyolefins, polyamides, fluoroplastics and others) are in their majority harmless and friendly to man [7]. Toxicity of this kind of plastics can arise from additives that are impregnated for special purpose or their decomposition products. The extent of the danger to the human organism of inhibited plastics during their production and application (independently of the purpose) depends on the toxicity of the low-molecular components that isolate into the environment. 

Though the gas number of ABFA is normally 220-260 cm /g, it can go up to 420 cm /g in the presence of catalysts. Azodicarbonamide is recommended for foaming of PVC, polyolefins, polyamides, polysiloxanes, epoxides, polymers and compolymers of acrylonitrile and acrylates, and rubbers. 

Though numerous types of plastics materials are presently used for automotive applications, future vehicles will probably use fewer resin variables. This consolidation trend is well underway and is a result of postconsumer recycling requirements (see Ghapter 6), which increasingly emphasize the use of only a few families of materials. Auto manufacturers will rely primarily on four key resin families for their plastics applications polyolefins, polyamides, polyurethanes, and styrenics. The future use of PVC for automotive applications is uncertain due to pressure of environmental groups who assert that the resin contaminates automotive shredder residue with chlorine. 

Polyolefin/polyamide blends can be used for a variety of applications where one polymer will enhance the properties of the other polymer. Research on these blends has so far been very fundamental, exploring different possibilities to compatibilize and improve the properties of otherwise very incompatible pol5miers. 

Uses Antioxidant for polyolefins, polyamides, polyesters, PVC, PS, rubbers, food-grade polymers impact modifier for PVC Regulatay FDA 21CFR 178.2010 Manuf./Dlstrlb. Aldrich Ciba Spec. Chems7/tddit. GE Spec. 

Uses Antioxidant for rubbers, SBR, polymers, polyacetals, linear saturated polyesters, PVC, polyolefins, polyamides antioxidant for food-... 

Uses Antioxidant stabilizer for styrenics, polyolefins, polyamide, PVC, urethane and acrylic coatings, adhesives, elastomers, cellulosics metal deactivator replaces BHT in polyolefins antioxidant, stabilizer in food-grade polymers, acrylic food pkg. in food-pkg. adhesives Regulatory FDA 21CFR 175.105,177.1010,178.2010 Manuf./Distrib. Aldrich Allchem Ind. ChemService Ciba Spec. Chems./ Addit. GE Spec. 

Toxicology LD50 (oral, rat) 6300 mg/kg TSCA listed Uses Antioxidant/stabilizer for polyolefins, polyamides, PU, PVC, PS, rubbers, cellulosics, food-grade polymers, food-pkg. adhesives antioxidant in lubricants for incidental food-contact use metal deactivator Regulatay FDA 21CFR 175.105,178.2010,178.3570 Manuf./Distrib. Ciba Spec. Chems./Addit. 

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