Films metallocene polyethylene

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. 

TABLE 3.3 Chemiluminescence Under Nitrogen at 170°C of Metallocene Polyethylene Films Containing the Nano and Micron Grade Titania Pigments at 0.5% w/w Concentrations with 0.05% w/w Irganox 1010 Antioxidant Together with Control Unpigmented Samples... 

FIGURE 3.4 First and second chemiluminescence peak curves versus time of metallocene polyethylene films free, stabilized with Irganox 1010 (0.05% w/w), and pigmented with micron- and nanoparticle titanium dioxide (0.5%), determined at 170°C under oxygen. 

FIGURE 2.10 Downgauging of polyethylene film in plastie garbage bag applications. Source Exxon Mobil Corporation. Life Cycle Assessment of Metallocene Polyethylene in Heavy Duty Sacks. ExxonMobil Chemieal Company May 2011. 

Polymers prepared by metallocene catalysts have special properties. Metallocene-polyethylene is an excellent film wrap and has excellent barrier properties to oxygen and moisture. Special polymers such as linear low-density polyethylene (LLDPE) which is a copolymer of ethylene and 1-butene (or 4-methyl-l-pentene) can be manufactured readily by the use of metallocene catalysts. LLDPE is a high strength film-forming polymer. 

Figure 8.2. Blocking force in metallocene polyethylene film vs. concentration of calcium carbonate. [Data from Ruiz, F. A., Modifying Film Conversion and End-use Characteristics with Mineral Reinforcement.]...

Setnescu, R., Kaci, M., Dehouche, N., Setnescu, T., Nasri, L., Zaharescu, T. Hydrothermal ageing of metallocene polyethylene films in presence of grafted amine stabilizers. Arab. J. Sci. Eng. 40, 69-80 (2015)... 

Metallocene-catalysed very low density polyethylene (m-VLDPE) has become available with densities of as low as 0.903. This is of use for sealing layers of multi-layer films since sealing can commence at lower temperatures than with conventional materials such as LLDPE and EVA (see Section 11.6) with the polymer seal exhibiting both cold strength and hot tack strength. 

As part of a multi-technique investigation (see also discussion under mid-infrared spectroscopy later), Corrales et al. [13] plotted the carbonyl index for films prepared from three grades of polyethylenes a high-density PE (HDPE), a linear low-density PE (LLDPE) and a metallocene PE (mPE) (see Figure 5). In this study, the data trend shown in Figure 5 correlated well with activation energies derived from the thermal analysis, which showed that the thermal-oxidative stability followed the order LLDPE > mPE > HDPE, whereas the trend... 

For films. Table 4.1 proposes an arbitrary classification of the polyethylene subfamilies (where m indicates metallocene catalysis). 

Beagan, C.M., McNally, G.M., and Murphy, W. R., Metallocene Catalysed Polyethylene in Blown Film Applications-A Comparison Between Monoextruded Blended Films and Coextruded Films, SPEANTEC Tech. Papers, 44, 128 (1998)... 

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