Plastic semirigid

A composite dmm is constmcted of a plastic, semirigid inner liner (usually polyethylene) and either a steel or fiber outer container or overpack. The composite dmm may be a useful compromise between a plastic dmm and a conventional steel dmm. It is strong enough to be handled like a steel dmm, yet provides an enclosure for chemicals that cannot be shipped safely in steel or fiber dmms. Capacities of composite dmms are 19—208 L (5—55 gal). Such dmms are used in chemical, pharmaceutical, and food industries. 

Plastic, semirigid Plastic having apparent modulus of elasticity in the range 10,000 to 100,000 psi at 23°C, as determined by the Standard Method of Test for Stiffness in Flexure Plastics (ASTM Designation D747). 

FDA. 1999c. U.S. Food and Dmg Administration. Code of Federal Regulations. 21 CFR 177.1010 Aciylic and modified acrylic plastics, semirigid and rigid. 

CFR 177.1010. Acrylic and Modified Acrylic Plastics, Semirigid and Rigidf ]... 

Acrylic and modified acrylic plastics, semirigid and rigid di-(2-ethylhe tyl) phthalate, for use only as a flow promoter at a level not to exceed 3 wt% based on the monomers and dimethyl phthalate... 

Polyethylene. The most straightforward process for the production of polymers from ethylene is that of the direct polymerization of the olefin. The polymerization process usually requires pressures and temperatures of 15,000 to 30,000 pounds per square inch and 200° to 300° C., and may be effected in either gas or liquid phase reactions (9). The polymer of molecular weight above 20,000 is the white, translucent plastic, polyethylene, widely used in electrical insulation, packaging material for foods, cosmetics and pharmaceuticals, liners for paper bags, etc. Articles molded from polyethylene are semirigid or rigid, depending on their thickness, but in thin films the material has excellent flexibility, even at relatively low temperatures. 

As condensation on the walls calls for supplementary evaporation, a thin wall is advisable. Most chambers are built of glass or semirigid plastic. These materials are thick, have low heat conductivity and high specific heat, as easily observed from the profuse condensation which runs in heavy drops from the wall. A thin transparent plastic sheet (PI) is a far cheaper cover and easy to handle. Only a very fine mist condenses on the sheet, and the possibility of using a high current density without the need for any cooling is proof of good functional conditions. 

Indirect food additive acrylic Use only as a flow and modified acrylic plastics, promoter at a level semirigid and rigid not to exceed... 

Ball-and-socket joints must be held together with either a metal spring type of clamp (like a clothespin) or a semirigid plastic clamp. Because ball-and-socket joints cannot be used without one or the other type of clamp, be sure to include the right-size clamp when ordering apparatus that have ball-and-socket parts, if they are not otherwise supplied. 

Suppositories [17]. Suppositories are semirigid and plastic dosage forms designed to be delivered to body cavities such as the rectum, vagina, or urethra. They either melt at body temperature (cocoa butter) or are dissolved in the fluid of the cavity (polyethylene glycols or glycerogelatin). Suppositories can be used for systemic therapy (rectal suppositories) or for local treatment. 

LVPs are usually provided in glass containers, flexible plastic bags, or semirigid containers. These systems are also classified as open systems (non-vacuum) and closed systems (vacuum). The largest manufacturers of LVPs are Abbott Laboratories, Baxter Healthcare Corporation, and B. Braun. 

Tin is frequently used in the production of aerosol cans by electroplating it onto sheet steel to improve corrosion resistance and facilitate soldering. In contrast, aluminum is used in its pure form as foil. Often, aluminum foil is used as an impermeable layer in a multilayer laminate that may include paper and plastics as well. Aluminum foil can be formed into rigid containers, semirigid containers, blister construction, or laminates. 

LVPs and small volume parenterals (SVPs) in plastic containers (flexible, semirigid, rigid) ... 

Carwinate []. TM for isocyanates used to make urethane elastomers, coatings, foam adhesives, rigid plastics, sealants, and one-shot flexible, semiflexible, and semirigid foams. 

Semipermeable containers Containers that allow the passage of solvent, usually water, while preventing solute loss. The mechanism for solvent transport occurs by absorption into one container surface, diffusion through the bulk of the container material, and desorption from the other surface. Transport is driven by a partial pressure gradient. Examples of semipermeable containers include plastic bags and semirigid, low-density polyethylene (LDPE) pouches for large volume parenteral (LVPs), and LDPE ampoules, bottles, and vials. 

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