Materials puncture resistance

General advice on the suitability and degree of resistance of glove materials are summarized in Table 13.12. In all cases, however, in addition to the necessary mechanical properties (i.e. resistance to abrasion, blade cut resistance, tear resistance and puncture resistance rated according to European Standard EN 388), consideration should be given to the resistance to the specific chemicals involved. 

Based on this analysis it is evident that materials which are biaxially oriented will have good puncture resistance. Highly polar polymers would be resistant to puncture failure because of their tendency to increase in strength when stretched. The addition of randomly dispersed fibrous filler will also add resistance to puncture loads. From some examples such as oriented polyethylene glycol terephthalate (Mylar), vulcanized fiber, and oriented nylon, it is evident that these materials meet one or more of the conditions reviewed. Products and plastics that meet with puncture loading conditions in applications can be reinforced against this type of stress by use of a surface layer of plastic with good puncture resistance. Resistance of the surface layer to puncture will protect the product from puncture loads. An example of this type of application is the addition of an oriented PS layer to foam cups to improve their performance. 

Mechanical Breakage. Mechanical breakage of packages can occur for several reasons. The materials may not have sufficient strength (heavy enough paper or film), puncture resistance may be insufficient, or one part of the structure may be too weak (or too strong) for the particular application. 

Bentonite clay expands when moist to create a waterproof barrier. Bentonite is sold in various forms, including panels and mats. Bentonite is not as resistant to chemicals as the thermoplastic membranes, nor is it puncture resistant. The major flaw of bentonite as a radon barrier, however, is that it is only tightly expanded when wet. This is acceptable for a waterproofing material, but not for a gas barrier. 

Polyethylene-coated kraft paper vapor barrier is available in 8 x 125 ft rolls. Overlaps of 6 in. are marked on the paper with a printed line. They can be sealed with polyethylene tape. This material is attractive to contractors because it is more puncture resistant than a 6-mil polyethylene construction film, but less expensive than many alternative products. 

Envelope material such as DuPont s Tyvek Stiffer than other polyethylene films Strong and puncture resistant... 

The PE separators have excellent microporous structure for electrolyte flow with minimal lead particle deposits excellent ductility, strength, and toughness for envelopability and plate puncture resistance excellent oxidation, chemical and thermal resistance to resist premature deterioration and good manufacturability with high production efficiency and relatively low raw material cost, which reduces overall manufacturing costs. The PE pocket sepa-... 

The specific material properties (e.g., high puncture resistance) of Ecovio F Film are very suitable for applications like loop-handle shopping bags. Some retailers in Europe have started to market loop-handle bags based on Ecovio F Film. 

Materials synthesis is a necessary component in the development of advanced technologies for national security and homeland defense. For instance, new composites, nanoscale molecules and compounds, and polymers are needed for tougher, explosion- or puncture-resistant materials that can be employed in buildings, garments, bridges, and other products and structures. Personal protective materials could be enhanced with new chemical adsorbents filter materials, impermeable membranes, artificial sutures, and improved energetic materials for... 

Material Abrasion Resistance Cut Resistance Flexibility Heat Resistance Ozone Resistance Puncture Resistance Tear Resistance Relative Cost... 

This process usually relies on the item or load rotating (e.g. a pallet) while the film reel is held vertically so that it can operate with a spiral motion. With simple hand wrapping, the operator walks around the item, applying layers which overlap in a spiral motion. Since these processes can only be applied to the sides of a pallet, a top sheet inserter may be employed to cover the top. This is then held in position by a stretch layer. The level of stretch achieved depends on the material employed, the uniformity of the load and the process employed. If a material is over-stretched i.e. the natural yield point is exceeded, the film becomes less puncture resistant and may break. Limits of stretch by these processes are around 50-60%. 

Braiding - The name of the process in which fluo-ropolymer tubes, wires, and cables are reinforced. Strands of metal and plastic and other thin wire shape materials are formed into braids and wrapped around the fluoropolymer tube or wire to improve pressure rating, and wear and puncture resistance. 

Objective Efficient Impact modification of mLLDPE film. Solution New modifiers based on a nonolefinic elastomer. The properties obtamable from PO film created with metallocene catalyst technology can result in consistent film materials with high toughness. Yet Impact-modification strategies can stlU be used to enhance the tear and puncture resistance of these films. And these Impact modifiers do not themselves need to be based on olefinic chemistries. 

Radioactive needles contaminated with infectious agents or blood should be autoclaved as described above, and then incinerated on site or shipped to a low-level radioactive waste site. To prevent injuries, it is important that hypodermic needles and other sharps be kept in waste containers that are puncture-resistant, leak-proof, and closable from the point of discard through ultimate disposal. To prevent airborne radioactive materials, destruction of needles by grinding or a similar means is not recommended. 

Ionomers are used in apphcations such as golf ball covers and bowling pin coatings, where their good abrasion resistance is important. The puncture resistance of films allows these materials to be widely used in packaging apphcations. One of the early applications was the packaging of fishhooks. They are often used in composite products as an outer heat-seal layer. Their ability to bond to aluminum foil is also utilized in packaging applications. Ionomers also find apphcation in footwear for shoe heels. ... 

Use puncture-resistant, leak-proof containers to collect, handle, process, store, transport, or ship blood specimens and potentially infectious materials. 

CR2320-type coin cells. Solupur materials showed low tortuosity, high strength and puncture resistance, excellent wettability, good high rate capability and low-temperature performance because of its high porosity and UHMWPE structure [68]. 

The force required to create a short through a separator due to mix (electrode material) penetration defines mix penetration strength. In this test, force (with a Vi.-inch diameter ball) is applied on the positive electrode/separator/negative electrode sandwich and the force at which the mix penetrates through the separator and creates an electronic short is called mix penetration force. Mix penetration strength is used to indicate the tendency of separators to allow short circuits during battery assembly. The mix penetration resistance test is more closely related to particle penetration resistance compared to puncture resistance [45]. 

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