Shrinkable films

Films stretch film, laminated film, shrinkable film... 

Thermoplastic Films. Recently, thermoplastic film [1342,1343] materials have been developed to reduce the proppant flowback that can occur after fracturing treatments. A heat-shrinkable film cut into thin slivers provides flowback reduction over broad temperature ranges and closure stress ranges... 

Heat-shrinkable films, 28 46 Heat shrinkable polymers, 22 364 Heat sinks, 26 756 silver in, 22 658 Heatsink slugs, 24 864 Heats of reaction, in DR Processes,... 

ICT machines produced recently have energy ratings from 0.3 to 3.0 MeV and beam power capabilities up to 100 kW. Nearly 180 of these machines, the majority of them rated for less than 1 MeV, have been installed as of the early 1990s. They are used mainly for cross-linking of heat-shrinkable film, plastic tubing, and electric wire. ... 

Heat-shrinkable films have found wide use in food wrap and packaging. The original development was done in the late 1950s by W. R. Grace and Co.,... 

Consumer products (packaging, shrinkable films and sheets, labels, displays, and CDs and DVDs)... 

An example system is PVC and polyethylene wire and cabling irradiated to improve stresscracking resistance, abrasion resistance, high-temperature properties and flame retardance, via controlled electron-beam crosslinking (Loan, 1977). Additionally electron-beam crosslinking is utilized to impart memory into a polymer system, such as crosslinked PE materials for heat-shrinkable films and pipe applications (Baird, 1977). The control of electron-beam processing has advanced the quality of cell size and shape of PE foams via control of crosslink distribution (Paterson, 1984). 

Relatively highly permeable to moisture, and fairly permeable to gases. Used for thermoforming (non-barrier usage) and as a shrinkable film on a limited basis. Relatively brittle material unless impact-modified when clarity reduces. 

Shrink and stretch wrapping—shrinkable films (PVC, polypropylene, polythene), sleeve or complete overwraps. Stretchable wraps, e.g. LLDPE, modified PEs. 

Metallocene LLDPE and ionomer heat shrinkable films Babrowicz Cl/., 1994... 

Shrinkablefilm and tubing Cross linked semicrystalline thermoplastics display rubberlike properties at temperatures above their melting points. On deformation followed by fast cooling the polymer maintains its deformed shape. The polymer returns to its original shape when reheated. This memory effect is applied in the production of heat shrinkable films and tubing. Radiation doses of the order of 40 — 1(X) kGy are used in the production of heat shrinkable products. 

Hsat-shrinkable film. [Data from Yoshiga, N. Nakamura, H. Ohmura, M., US Patent 4,264,010, Apr. 28,1981.]... 

These blends are widely used in shrinkable films, multilayer packing, and wire and cable coating. Although PE and EVA are immiscible, the vinyl consequence in EVA gives the same crystal structure as PE and partial miscibility at the interface of PE/EVA blends. Addition of EVA to HOPE could improve transparency, environmental stress cracking resistance, capacity of filler carrying, and impact properties, but usually reduces the tensile strength. 

Viksne, A., Zicans, J., KaUds, V, Bledzki, A. K., Heat-shrinkable films based on polyolefin waste. Die Angewandte Makromolekulare Chemie 1997,249,151-162. 

Cell morphology of foamed PVC depends on concentration of a plasticizer, surface treatment of filler and foaming time and temperature. High concentrations of plasticizers produced poly disperse cell structure. Polyester plasticizer blends are useful for production of heat-shrinkable film. Plasticizer migration from geomembranes causes membrane shrinkage. ... 

Ethylene can be free radically copolymerized with vinyl acetate. Copolymerization with 0%-35% vinyl acetate is carried out in bulk at 1000-2000 bar, that of 35%-100%at 100-400 bar in /-butanol, and that of 60%-100%at 1-200 bar in emulsion. Products with vinyl acetate contents of over 10% give shrinkable films those with up to 30% vinyl acetate give thermoplastic films, and those with over 40% vinyl acetate give clear films. Products of still higher vinyl acetate content are elastomers, fusion, and solvent adhesives or modifiers for PVC. The products can be cross-linked with lauroyl peroxide on the addition of, for example, triallyl cyanurate. Copolymers of ethylene and ethyl acrylate have similar properties. 

Semicrystalline polyethylenes cross-link only in the amorphous regions. After sufficient cross-linking, the polymer does not flow any more. Typical polymers that can be cross-linked similarly are polypropylene, polystyrene, poly acrylates, and poly(vinyl chloride). Uses of the cross-linked polymer include wire and cable insulation, heat-shrinkable films and tubing. 

Heat-shrinkable film comprised single-site catalyzed Babrowicz et al. (1994) copolymer of ethylene and a 3-8C alpha-olefin, LLDPE with p > 9(X) kg m blended with another polymer of ethylene and a 3-8C alpha-olefin and a second comonomer [e.g., vinyl acetate, alkyl acrylate, CO, butadiene, styrene, acrylic acid, and a metal salt of an acrylic acid], or an alpha-olefin homopol3uner. The films had improved shrinkability, impact resistance, and optical properties as compared to prior art and were used in packaging... 

First polyethylene-polyethylene, PE/PE, blends were patented both cross-linked (using electron accelerators) and uncross-linked components were disclosed. In Phillips patent, low-density polyethylene, LDPE, was blended with linear low-density polyethylene, LLDPE, for unproved stiffiiess and abrasion resistance and reduced water vapor permeability, fir the Celanese patent, improvement of processability was particularly stressed. In the DuPont patent, 10-50 wt% LLDPE was used with LDPE or its copolymers for generating heat-shrinkable films... 

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