Properties puncture resistance

In general, LDPE provides film with better optical properties e.g., clarity and haze) and is easier to process. However, films made from LLDPE or HDPE display better mechanical properties (puncture resistance, tear strength, etc.), though they are more difficult to process. For this reason, LDPE is sometimes used as blend-stock with LLDPE and HDPE (18). The blended composition becomes easier to process while retaining good mechanicals. 

Linear Low Density Polyethylene. Films from linear low density polyethylene (LLDPE) resias have 75% higher tensile strength, 50% higher elongation-to-break strength, and a slightly higher but broader heat-seal initiation temperature than do films from LDPE. Impact and puncture resistance are also improved over LDPE. Water-vapor and gas-permeation properties are similar to those of LDPE films. 

Even though separation may not be the primary function for which the geotextde is instaded, in almost every case the geotextde does perform as a separator. For the separation function, the physical properties of concern are primarily strength-related, including wide width, puncture resistance, and tear resistance. 

Film. By far the largest appHcation for LLDPE resins (over 60% in the United States) is film. Because LLDPE film has high tensile strength and puncture resistance, it is able to compete with HDPE film for many uses. The toughness and low temperature properties of LLDPE film also exceed those of conventional LDPE. Furthermore, because LLDPE resins exhibit relatively low strain hardening in the molten state and lower extensional viscosity, it can be produced at high rates with Httle risk of bubble breaks. 

It is generally claimed that metallocene polyethylenes (often abbreviated to m-PE) exhibit superior mechanical and optical properties as well as better organoleptic properties (resulting from the lower residue levels). As an example m-LLDPE is particularly favoured as a stretch film for wrapping because of the good prestretchability, high puncture resistance and tear strength, all of which are claimed to be better than with conventional LLDPE. 

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. 

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. 

General Description Ethylene Vinyl Acetate (EVA) Copolymer is a copolymer resin ranging in vinyl acetate content from 7.5 wt% to 33 wt%. DuPont Elvax and Equistar Ultrathene grades vary by vinyl acetate content. Some grades are available with antiblock and slip additives. The vinyl acetate units in the copolymer modify the basic polyethylene structure and its properties. The addition of vinyl acetate to polyethylene provides lower sealing temperature, increased flexibility, improved optical properties, greater adhesion, increased impact, and puncture resistance. 

Kraton polymers blended with polypropylene can provide films with elasticity and strength, puncture resistance, low permanent set to prevent finger marks and indentation due to handling, high oxygen permeability, moisture-barrier properties, and clingJ ]... 

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. 

Alternatively, by preventing thermal degradation, heat stabilizers also have the effect of keeping die surfaces clean, increasing throughput, and maximizing film properties, such as tear and puncture resistance Cel-Span 306P is a 6% stabilizer concentrate offered for this purpose from Phoenix Plastics, for use... 

Geotextile function Tensile strength Elongation Chemical resistance Biode- gradability Flexibility Friction property Interlock Tear resistance Penetration Puncture resistance... 

American National Standard provides guidance for selecting suitable gloves that will protect workers and assist employers in compliance with OSHA Regulation 29 CFR 1910. The standard covers glove selection criteria in specific categories related to testing and performance properties in chemical and industrial applications, such as cut method puncture resistance abrasion... 

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