Polyolefin plastic

These rubbers are now also being blended on a large scale with polyolefin plastics, particularly polypropylene, to produce a range of materials which at one extreme are tough plastics and at the other the so-called thermoplastic polyolefin rubbers (TPORs) (.see Section 11.9.1). 

Polyolefins Plastics such as polyethylene (PE), polypropylene (PP), and polybutylene (PB) that are derived from unsaturated hydrocarbons (also called olefins). 

This reports on a process developed at the University of Tokyo to convert waste polyolefin plastic into a mixture of high quality fuels. Details of the process, which uses a carbon catalyst, are given. 

Polymerised propylene, a polyolefin plastic with properties similar to those of polyethylene. Polypropylene Glycol (PPG)... 

Guess WL, Haberman S. 1968. Toxicity profiles of vinyl and polyolefinic plastics and their additives. J Biomed Mater Res 2 313-335. 

Marcato, B., Guerra, S., Vianello, M. and Scalia, S. (2003). Migration of antioxidant additives from various polyolefinic plastics into oleaginous vehicles, Int. J. Pharm., 257, 217-225. 

T. O. Kresser, Polyolefin Plastics, Van Nostrand-Ranhoid. New York (1969). 

Larger 3- and 4-m.e.v. Dynamitron electron beam accelerators are likewise available commercially. Service capabilities increase with the m.e.v. level of the electron beam accelerator. A 3.0-m.e.v. Dynamitron electron beam accelerator furnishes radiation capable of penetrating a maximum 370 mils of a unit density material or 185 mils of 2.0-density material other performance capabilities are doubled as well. The overwhelming majority of polyolefin plastic products now being manufactured have section thicknesses which can be penetrated safely even by a 1.5-m.e.v. electron beam accelerator. Two possible exceptions would be printed circuit board and thick-walled pipe. A 3-m.e.v. accelerator could readily meet such requirements. The performance capabilities of the 3-m.e.v. accelerator (12-ma. power supply) are increased not only with respect to maximum depth of penetration but also processing capability, which amounts to 14,000 megarad-pounds per hour at 50% absorption efficiency. 

Transmaterialisation is a more fundamental approach to the problem, which, with the goal of sustainable development, would ultimately switch consumption to only those resources that are renewable on a short timescale. Clearly petroleum, which takes millions of years to form, is not an example of such a sustainable resource. For the method to be truly effective, the wastes associated with the conversion and consumption of such resources must also be environmentally compatible on a short timescale. The use of polyolefin plastic bags for example, which have lifetimes in the environment of hundreds of years, is not consistent with this (no matter how they compare with alternative packaging materials at other stages in their lifecycle), nor is the use of some hazardous process auxiliaries which are likely to cause rapid environmental damage on release into the environment. 

Ethylene Copolymers. Ethylene copolymers probably are the most important materials in hot-melt formulations. Ethylene-vinyl acetate and ethylene-ethyl acrylate polymers are very versatile and available in a wide range of grades offering different co-monomer contents and viscosities. The melts are stable and compatible with various modifying resins, waxes, extenders, and fillers. Adhesion to many substrates is good—including the polyolefin plastics, which are difficult to bond with most other types of adhesive unless the surfaces are pre-treated. 

The range of uses for polyolefin plastics, and for polypropylene in particular, has been expanded greatly in recent years one application of interest in this context comprised large mouldings (approximately 1 m by 0.5 m in area) designed to interlock and to be placed on football grounds or other sports fields... 

With conventional paint systems rather poor adhesion is obtained with acetal and the polyolefin plastics adhesion with polyamide normally is good at first but under adverse conditions can deteriorate. In general, ABS and polycarbonate do not give comparable difficulties. 

Epoxy and nitrile-phenolic adhesives have been used to bond polyolefin plastics after plasma surface preparation. Shear strengths in excess of 3000 psi have been reported on... 

Metallocene catalysts are the latest innovations to make a big impact in the polymer industry. They have been used mostly to make new polyolefin plastics, such as very-high-molecular-weight, bullet-proof polyethylene, but they have also been used to make elastomers. The catalysts make very regular stereospecific polymers similar to the Ziegler-Natta catalysts. 

K. Hyche, R. Hollis, Eastman Chemical Company, Preliminary Studies of Improved Dispersing Aids for Fluorescent Pigments in Polyolefin Plastics . Technical Conference of the Society of Plastics Engineers, Oak Brook, IL., P. 148. 

Pyrolysis treatments are interesting regarding the aforementioned plastic refuse makeup. Other successful treatments for feedstock recycling of condensation polymers (PET, ABS, etc.), that allows for the depolymerization and recovery of their constituent monomers (e.g. hydrolysis, alcoholysis, methanolysis, etc.), cannot be applied for polyolefin plastics recycling. In contrast, pyrolysis of polyolefins yields valuable hydrocarbon mixtures of... 

Oxidation inhibitor in natural and synthetic rubbers, polyolefin plastics, resins, adhesives, petroleum oils, and waxes. 

Ethanox 703 antioxidant is used as an oxidation inhibitor in natural and synthetic elastomers, polyolefin plastics, resins, adhesives, petroleum oil and waxes. Applications include steam turbine oils, hydraulic fluids, transformer oils, industrial gear oils and greases. 

The permeability test samples were five-layer polyolefin plastic cylindrical containers with EVOH as the barrier material, modified adhesive layers on either side of the EVOH, and polyolefin layers as outer protection. The EVOH used was Evalca s EPF which has 32 mole percent ethylene. The layer thicknesses In the container sidewalls were 14/1/2/1/14 mils. 

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