Polypropylene resins, densities

This versatile technique is generally used where a ply of polyethylene or copolymer thereof is required in a structure. Other polymers may be used in specialized areas but the handling can become more difficult. The process is widely used within the Packaging Industry for the coating of paper, board, foils, cellulose film and thermoplastic films. The most common coating resin used is low-density polyethylene, but this now extends to copolymers such as Ethylene-vinyl acetate, ethylene-acrylic acid, polypropylene, high density polyethylene and ionomers (e.g. Surlyn). The acrylic acid-based materials and ionomers are used in areas in which enhanced adhesive strength is required, such as resistance to difficult environments. 

Figure 21.3 Densities of six polypropylene resins with different melt flow rates, foamed with 3% Expancel 098 DUX 120 and injection molded at four different temperatures. Initial density...

Petrothene, Low-, medium- and high-density polyethylene and polypropylene resins, Equistar Chemicals... 

This plastics plant produces a number of resins, including high-density polyethylenes, which are used in the stiff material for Ariel bleach bottles and, indeed, coatings for industrial pipelines. Another product manufactured by LyondellBasell is the polypropylene resin Clyrell EC340R, marketed as ideal for high-impact, low temperature-resistant food containers. It is materials such as this that are ideal for moulding into Carte D Or ice cream boxes. 

The list of flexible polymeric roll materials suitable for atmospheric plasma processing is expansive. Mainstream resin types include polypropylene (homopolymers, heterophasic copolymers, and random copolymers), polyethylene (low, medium, and high density polyethylene resins), a family of specialty polyolefins which includes polybutene-1, advanced polypropylene resins from in-reactor alloying processes and polypropylene compounds, and fiuoropolymers. By process type, these materials (in mono- or multiple layers) can be generally represented by the following ... 

This type of adhesive is generally useful in the temperature range where the material is either leathery or mbbery, ie, between the glass-transition temperature and the melt temperature. Hot-melt adhesives are based on thermoplastic polymers that may be compounded or uncompounded ethylene—vinyl acetate copolymers, paraffin waxes, polypropylene, phenoxy resins, styrene—butadiene copolymers, ethylene—ethyl acrylate copolymers, and low, and low density polypropylene are used in the compounded state polyesters, polyamides, and polyurethanes are used in the mosdy uncompounded state. 

Table 6 shows the sales estimates for principal film and sheet products for the year 1990 (14). Low density polyethylene films dominate the market in volume, followed by polystyrene and the vinyls. High density polyethylene, poly(ethylene terephthalate), and polypropylene are close in market share and complete the primary products. A number of specialty resins are used to produce 25,000—100,000 t of film or sheet, and then there are a large number of high priced, high performance materials that serve niche markets. The original clear film product, ceUophane, has faUen to about 25,000 t in the United States, with only one domestic producer. Table 7 Hsts some of the principal film and sheet material manufacturers in the United States.

Thermoplastics. The highest consumption of color concentrates is in thermoplastic resins, such as low and high density polyethylene, polypropylene, PVC, and polystyrene. Processing techniques for thermoplastics are usually based on dry color dispersion in a compatible resin (36). 

Blends of isobutylene polymers with thermoplastic resins are used for toughening these compounds. High density polyethylene and isotactic polypropylene are often modified with 5 to 30 wt % polyisobutylene. At higher elastomer concentration the blends of butyl-type polymers with polyolefins become more mbbery in nature, and these compositions are used as thermoplastic elastomers (98). In some cases, a halobutyl phase is cross-linked as it is dispersed in the polyolefin to produce a highly elastic compound that is processible in thermoplastic mol ding equipment (99) (see Elastomers, synthetic-thermoplastic). ... 

In the mid-1950s a number of new thermoplastics with some very valuable properties beeame available. High-density polyethylenes produced by the Phillips process and the Ziegler process were marketed and these were shortly followed by the discovery and rapid exploitation of polypropylene. These polyolefins soon became large tonnage thermoplastics. Somewhat more specialised materials were the acetal resins, first introduced by Du Pont, and the polycarbonates, developed simultaneously but independently in the United States and Germany. Further developments in high-impact polystyrenes led to the development of ABS polymers. 

Resins and plastics such as low-density polyethylene (LDPE), high-density polyethylene (HOPE), linear low-density polyethylene (LLDPE), polypropylene, polystyrene, and polyvinyl chloride (PVC) ... 

Additive-free film samples of isotactic polypropylene (iPP, 30pm Himont Profax resin) and polyethylenes (LLDPE, 120ym, linear low density DuPont Sclair resin, and UHMW-PE, 120wm, ultra high molecular weight, high density Himont LSR 5641-1B resin) were oxidized by exposure in air to y-radiation (AECL Gamma Cell 220, 1.0... 

Those are the generalities of polymers. The specifics of low- and high-density polyethylene, polypropylene, polyvinyl chloride, and polystyrene are covered in the next chapter and resins and fibers in the last. 

The most common litter item are small pieces of plastics whose lengths are on the order of a few millimeters. An important component are thermoplastic resin pellets and beads that are raw materials, mostly polypropylene and polyethylene, intended for manufecture into commercial items. Loss during ship transport and stormwater runoff are major sources of the pellets and beads to the ocean. Densities of 3500 per km have been reported floating on the surfece in the Sargasso Sea. On the beaches of New Zealand located near industrialized areas, concentrations as high as 100,000 per km are now being observed. The pellets and beads are carried by currents until they are either... 

Industry estimates indicate that up to 5% of the total resin production finds its way into prototype or mill shape plastic products. By mill shapes is meant those primary uniform configuration subject to established cross-sectional and length tolerances. While this estimate is necessarily conjectural, the best available information indicates that this range is accurate. Modem Plastics magazine estimated mill shape production for 1968 in acrylics, cellulose, nylon, acetal, polycarbonate, high density polyethylene, polypropylene, poly(vinyl chloride), and copolymers to approach 336.4 million pounds. Total United States resin production for 1968 slightly exceeded 16 billion pounds. 

ABA ABS ABS-PC ABS-PVC ACM ACS AES AMMA AN APET APP ASA BR BS CA CAB CAP CN CP CPE CPET CPP CPVC CR CTA DAM DAP DMT ECTFE EEA EMA EMAA EMAC EMPP EnBA EP EPM ESI EVA(C) EVOH FEP HDI HDPE HIPS HMDI IPI LDPE LLDPE MBS Acrylonitrile-butadiene-acrylate Acrylonitrile-butadiene-styrene copolymer Acrylonitrile-butadiene-styrene-polycarbonate alloy Acrylonitrile-butadiene-styrene-poly(vinyl chloride) alloy Acrylic acid ester rubber Acrylonitrile-chlorinated pe-styrene Acrylonitrile-ethylene-propylene-styrene Acrylonitrile-methyl methacrylate Acrylonitrile Amorphous polyethylene terephthalate Atactic polypropylene Acrylic-styrene-acrylonitrile Butadiene rubber Butadiene styrene rubber Cellulose acetate Cellulose acetate-butyrate Cellulose acetate-propionate Cellulose nitrate Cellulose propionate Chlorinated polyethylene Crystalline polyethylene terephthalate Cast polypropylene Chlorinated polyvinyl chloride Chloroprene rubber Cellulose triacetate Diallyl maleate Diallyl phthalate Terephthalic acid, dimethyl ester Ethylene-chlorotrifluoroethylene copolymer Ethylene-ethyl acrylate Ethylene-methyl acrylate Ethylene methacrylic acid Ethylene-methyl acrylate copolymer Elastomer modified polypropylene Ethylene normal butyl acrylate Epoxy resin, also ethylene-propylene Ethylene-propylene rubber Ethylene-styrene copolymers Polyethylene-vinyl acetate Polyethylene-vinyl alcohol copolymers Fluorinated ethylene-propylene copolymers Hexamethylene diisocyanate High-density polyethylene High-impact polystyrene Diisocyanato dicyclohexylmethane Isophorone diisocyanate Low-density polyethylene Linear low-density polyethylene Methacrylate-butadiene-styrene... 

Fig. 1. US total sales and captive use of selected thermoplastic resins by major market for 2001. Major market volumes are derived from plastic resins sales and captive use data as compiled by VERIS Consulting, LLC and reported by the American Plastics Council s Plastic Industry Producers Statistics Group. Selected thermoplastics are low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, nylon, polyvinyl chloride, thermoplastic polyester, engineering resins, acrylonitrile-butadiene-styrene, styrene-acrylonitrile, other styrenics, polystyrene, and styrene butadiene latexes. (Data from ref. 25.)...

---