Properties Of Low-density Polyethylene Films Research Articles

Evaluation and effect of rice bran and microwave heating on the physicomechanical properties of low-density polyethylene film and packaged milk quality

Low-density polyethylene (LDPE) film was developed with a mixture of reference LDPE and rice bran (RB). Three mixtures of 5, 10, and 15% RB were used for the LDPE film preparation. The films were analysed for the physico-mechanical properties before microwave heating (MH) and after MH and packaged milk quality was analysed regarding MH and pasteurisation. After MH, the physicomechanical properties of the material change significantly. LDPE film containing 15% RB was created to beat changes in tensile strength, elongation at break, bursting strength, and water vapour transmission rate (WVTR). The total migration of tested packaging materials was within the agreeable limit and after MH it also was within the permissible limit. Four different simulators were used to create food categories. These food simulators included distilled water, 3% acetic acid, 50% alcohol (ethanol), and n-heptane. The obtained results display that the total migration of food packages is dependent on the MH period, package material, and the simulator.

Biodegradation efficacy of soil inherent novel sp. Bacillus tropicus (MK318648) onto low density polyethylene matrix

The biodegradation of low density polyethylene (LDPE) was studied by employing a microbial strain isolated from the dumping site soil. The bacterium strain was identified as Bacillus tropicus (Gen Bank Accession no: MK318648) by 16S rRNA sequencing. The growth of the strain was observed on virgin LDPE during the biodegradation process. The change in properties of LDPE films before and after bacterial strain incubation was observed by FTIR, SEM, AFM, contact angle, mechanical and optical testing. Loss in mechanical properties and changes in optical properties of the polymer matrix was observed. Weight reduction by 10.15% and fall in the value of tensile strength, elongation at break, tear strength, Young’s Modulus, hardness and stiffness to 8.59 MPa, 10.85 mm, 69.18 N, 272.36, 37.6 Shor D and 10,672.21 N/m respectively were observed after 40 days of incubation. The transparency and haze percentage were also changed to 93.7% and 18.6% respectively after the study period. The pH of the media was measured during incubation to evaluate the change due to formation of different extracellular and intracellular enzymes excreted by the strain. Hence, Bacillus tropicus could be an efficient microorganism to degrade 10-micron thickness LDPE films, thereby preventing its harmful impacts in the environment.

Low-Density Polyethylene Films Carrying ferula asafoetida Extract for Active Food Packaging: Thermal, Mechanical, Optical, Barrier, and Antifungal Properties

The physical, thermal, mechanical, optical, microstructural, and barrier properties of low-density polyethylene films (LDPE) containing ferula asafoetida leaf and gum extracts were investigated. Results showed a reduction in elasticity and tensile strength with increasing extract concentration in the polymer matrix. The melting temperature and enthalpy increased with increasing concentration of extracts. The films containing extracts had lower L∗ and a∗ and higher b∗ indices. The films containing leaf extract had more barrier potential to UV than the gum extracts. The oxygen permeability in films containing 5% of leaf and gum extracts increased by 2.3 and 2.1 times, respectively. The morphology of the active films was similar to bubble swollen islands, which was more pronounced at higher concentrations of gum and leaf extracts. FTIR results confirmed some chemical interactions of ferula extracts with the polymer matrix. At the end of day 14th, the growth rate of Aspergillus niger and Saccharomyces cerevisea in the presence of the PE-Gum-5 reduced more than PE-Leaf-5 (3.7 and 2.4 logarithmic cycles, respectively) compared to the first day. Our findings showed that active LDPE films have desire thermo-mechanical and barrier properties for food packaging.

The physical – mechanical properties of low-density polyethylene films

Polyethylene (PE) is the most commonly used polymer. Most of the polymers are processed by the packaging sector. PE products are the most recycled plastic due to the short life of packaging materials. The experiment is based on real issues in the recycling of plastic waste in a world that is increasingly up to date. One way of recycling it is to produce returnable plastic bottles that can be used up to 50 times. The low-density polyethylene (LDPE) film is applied to the plastic bottles before filling with a specific medium. After the contents of the bottle have been consumed, the LDPE film is stripped. Subsequently, a new recyclable film is applied to the bottles used and the process is repeated. Changes in the properties of LDPE films applied to these returnable bottles have been evaluated by several tests (tensile test and water absorption test). The tests were performed on unused LDPE films and on used LDPE films, which were filled with the medium for 3 months. The fill media was chosen from commonly available goods.

Effect of Tio2 Nanoparticles on the Antibacterial and Physical Properties of Low-Density Polyethylene Film

ABSTRACTIn this study, TiO2 nanoparticles were incorporated into low-density polyethylene by melt blending. Morphological properties and dispersion behavior of TiO2 nanocomposite were characterized through field emission scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectroscopy. Thermal stability of the nanocomposites was determined by thermogravimetric analysis. Moreover, the mechanical properties of nanocomposites were determined. Antimicrobial activity of TiO2 nanocomposites was investigated by in vitro test. Dispersion of the nanoparticles was good in nanocomposites. According to thermogravimetric analysis, incorporation of TiO2 nanoparticles into low-density polyethylene enhanced the thermal stability. Mechanical properties of nanocomposites were improved by TiO2 nanoparticles. Results showed that the antibacterial effect of low-density polyethylene –TiO2 nanocomposite was significantly enhanced by TiO2nanoparticles (p < 0.05). The number of surviving bacteria was decreased considerably. Finally, this study showed that the TiO2 nanoparticles not only can improve the properties of low-density polyethylene but they also have the potential to be used as an active food packaging film.

Engineering and antibacterial properties of low-density polyethylene films with incorporated epigallocatechin gallate

The antibacterial activity of low-density polyethylene/adhesive resin (10%)/epigallocatechin gallate (0.03, 0.5, 5, and 10%) extrusion cast films were evaluated against Staphylococcus aureus (gram positive) and Pseudomonas sp. (gram negative) via direct contact and in solid and liquid culture media. The epigallocatechin gallate concentration in the active films was established per the in vitro antibacterial analysis of pure epigallocatechin gallate against S. aureus and Pseudomonas sp. The epigallocatechin gallate migration profile and concentration required to inhibit bacterial growth in broth were determined. In addition, the effects of epigallocatechin gallate and adhesive resin on the mechanical, color, and thermal film properties were investigated. The results indicate that pure epigallocatechin gallate inhibited the growth of both bacteria. However, only the films with 10 wt% epigallocatechin gallate (with and without adhesive resin) induced morphological changes and inhibited the growth of S. aureus (p &lt; 0.05). In addition, the films with 10 wt% epigallocatechin gallate (with adhesive resin) induced morphological changes in Pseudomonas sp. (p &lt; 0.05). The adhesive resin increased the epigallocatechin gallate release rate in the migration profile (p &lt; 0.05). The epigallocatechin gallate and adhesive resin modified the film properties (p &lt; 0.05). Fourier transform infrared analysis indicated hydrogen bonds between the adhesive resin and epigallocatechin gallate. This study demonstrated that epigallocatechin gallate is a potential antibacterial agent and that adhesive resin provides advantages to active films.

Effect of Ar bombardment on the electrical and optical properties of low-density polyethylene films

The influence of low-energy Ar ion beam irradiation on both electrical and optical properties of low-density polyethylene (LDPE) films is presented. The polymer films were bombarded with 320 keV Ar ions with fuences up to 1×1015 cm−2. Electrical properties of LDPE films were measured and the effect of ion bombardment on the DC conductivity, dielectric constant and loss was studied. Optically, the energy gap, the Urbach’s energy and the number of carbon atoms in a cluster were estimated for all polymer samples using the UV–Vis spectrophotometry technique. The obtained results showed slight enhancement in the conductivity and dielectric parameters due to the increase in ion fluence. Meanwhile, the energy gap and the Urbach’s energy values showed significant decrease by increasing the Ar ion fluence. It was found that the ion bombardment induced chain scission in the polymer chain causing some carbonization. An increase in the number of carbon atoms per cluster was also observed.

Characterization and properties of LDPE film with gallic‐acid‐based oxygen scavenging system useful as a functional packaging material

ABSTRACTWe prepared and characterized active, oxygen‐scavenging, low density polyethylene (LDPE) films from a non‐metallic‐based oxygen scavenging system (OSS) containing 1, 3, 5, 10, and 20% of gallic acid (GA) and potassium chloride (PC). We compared the surface morphology and mechanical, permeability, and optical properties of the oxygen‐scavenging LDPE film with those of pure LDPE film. The surface morphology, gas barrier, and thermal properties indicate that the OSS was well incorporated into the LDPE film structure. The surface roughness of the film increased with the amount of oxygen scavenging material. The oxygen and water vapor permeability of the developed film also increased with the amount of oxygen scavenging material, though its elongation decreased. The oxygen scavenging capability of the prepared film was analyzed at different temperatures. The initial oxygen content (%) in the vial headspace, 20.90%, decreased to 16.6% at 4 °C, 14.6% at 23 °C, and 12.7% at 50 °C after 7 days of storage with the film containing 20% OSS. The film impregnated with 20% organic oxygen scavenging material showed an effective oxygen scavenging capacity of 0.709 mL/cm2 at 23 °C. Relative humidity triggered the oxygen scavenging reaction. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44138.

Effect of Low-Temperature Plasma Treatment on Surface Properties of LDPE Film

Low-density polyethylene (LDPE) film was treated by low-temperature plasma. Scanning electronic microscope, electronic universal testing machine, contact angle/interfacial tension measuring instrument were used to analyze the surface morphology, surface contact angle, bonding strength and performance of LDPE film before and after they were treated by low-temperature plasma. The results show that air ambience is more appropriate than N2, CO2 for treatment. Specifically, plasma treatment in air ambience, under conditions of 44 W (power), 30 s (duration) and 60 Pa (vacuum degree), can decline static contact angle of LDPE film from 101° to 13.5°. The transiency of plasma-treated LDPE film is so obvious that storage time of longer than one hour will result in a contact angle up to 74° and loss of plasma treatment effect (timeliness). Therefore, the reversible plasma-treated LDPE film should be processed immediately.

Influence of Natural and Accelerated Weathering on the Mechanical Properties of Low-Density Polyethylene Films

Natural and accelerated weathering tests were performed to inspect the effect of antioxidants on low-density polyethylene (LDPE) films used as greenhouse covering materials. The LDPE pellets were extruded and blown into a film using a twin-screw extruder and film blowing machine, respectively. The film with 0.2 wt.% Alkanox-240 (AN-0.2) stabilizer showed the highest tensile strength (11 MPa) among all samples during 90 days of natural as well as accelerated weathering. The elastic modulus of the film with 0.5 wt.% of Good-rite (GR-0.5) increased after weathering from approximately 91.8 to 138.9 MPa, and showed the best performance. Morphological images of the neat LDPE film during weathering showed some cracks and grooves, while those of stabilized films showed fewer cracks. Moreover, the estimation of the rapidity of the accelerated method compared to the natural one was approximately nine times faster in Riyadh during the summer season (June–August). The present study suggests that the addition of antioxidants can improve the tensile strength, stability, and, hence, the effectiveness of these films. The best antioxidants were found to be 0.2 wt.% Alkanox and 0.5 wt.% Good-rite antioxidants.

Characterization on Optical and Mechanical Properties of Low-Density Polyethylene Films Doped with Eu(III) Complex

Low-Density Polyethylene films of 100 μm thickness doped with Eu (TTA)3phen complex was hot-blown by a lab scale extrusion process. The ratio of the complex was varied from 0%, 0.025%, 0.5%, 0.1%, to 0.2% with respect to the total weight of LDPE. The mechanical properties of the films were measured according to ASTM D882, and ASTM D1938 standards. The optical and chemical properties were characterized by spectrofluorometer and FTIR respectively. FTIR characterization shows that Eu (TTA)3phen in LDPE films does not exhibit spectrum due to the dominant nature of amorphous LDPE. All emission transition lines of Eu3+ion for doped films were observed when excited at 394 nm, and the highest peak was detected at 608 nm. The peak intensity reached a saturation level at 0.1% doping ratio, while mechanical test showed that the tensile strength (TS) and elongation at break (EB) of machine direction (MD) oriented films decreased with increasing ratio of the complex, in which at doping ratio of 0.2%, both values dropped by 17.8% and 11.6% respectively.. These results indicate that different doped ratio of Eu (TTA)3phen affect significantly the film properties which offer possibility for an improved photoselective greenhouse plastic films. Keywords; LDPE, Eu (TTA)3phen, Photoluminescence.

Effect of UV Treatment on Optical Properties of Low-Density Polyethylene Films Doped with Eu(TTA)&lt;sub&gt;3&lt;/sub&gt;phen Complex

Low-Density Polyethylene (LDPE) films doped with Eu (TTA)3phen complex (TTA=2-thenoyltrifluoroacetone, phen=1,10-phenanthroline) were fabricated by hot-blowing technique for thickness of 100 μm. The films were doped with 0.1 % of Eu (TTA)3phen to the total weight of LDPE and exposed to UV irradiation from deuterium lamp for 5, 10, 20, 40 and 60 hours to investigate the effect of its optical properties. The films were characterized by Spectrofluorometer, UV/VIS Spectrophotometer and FT-IR Spectrometer to measure their emission spectra, lifetimes, transmission transparency and chemical bonding. Photoluminescence of the room-temperature Eu (TTA)3phen doped films consist of typical Eu3+emission transition lines with hypersensitive5D07F2emission band at 610 nm. After 20 hours UV treatment, the peak intensity dropped by 90 % and shortened the luminescent lifetimes from 0.654 ms to 0.305 ms. Longer UV treatment also has accelerated degradation in doped LDPE films shown by significant reducing in absorption peak of FTIR at 3395, 3186 and 1645 cm-1. The results would provide a mechanism to improve the lifetime of the LDPE by utilizing the light-manipulation property of Eu (TTA)3phen complex to absorb UV spectrum and covert into red emission.Keywords: LDPE, rare-earth complex, photoluminescence

LDPE/EVA Modified Film Prepared by Melt Blend Method and Study of its Mechanical Performances and Barrier Property

In this study, six kinds of different films from LDPE (Low-density polyethylene) modified by EVA (Ethylene - vinyl acetate copolymer) were made, and EVA / LDPE mass ratio was 0/50, 1/49, 1/ 19 4/21, and 1/3. Influence of EVA amount on the properties of LDPE film was investigated using the Instron universal testing machine, DSC, oxygen permeability tester and breathable apparatus. The mechanical properties of the blended films showed that when the EVA content was 5%, LDPE / EVA film transverse Young's modulus increased by about 50%, and the vertical Young's modulus increased by about 56%, which is good for improving the overprint accuracy of the LDPE / EVA film. DSC analysis showed that the melt blending has no effect on the thin-film processing temperature and thermal stability, but the result indicated that the crystallinity of the blended films was lowered with the increase of EVA amount. Barrier tests showed that with the increase of EVA content, the barrier of the modified films was decreased. The polarity of the film increased with more EVA component, which would augment the surface tension of LDPE and its ink adhesion.

Mechanical and surface properties of low-density polyethylene film modified by photo-oxidation

The use of biodegradable polyethylene can help reduce accumulation of inert polyethylene in the environment, as well as soil pollution. The incorporation of pro-oxidant additives into polyethylene makes the polymer susceptible to physical damage caused by photolysis and chemical oxidation, rendering a reduction in physical strength. The scanning electron microscope photograph of 20% oxo-biodegradable additive-added polyethylene showing the physical damage as a larger hole of 9.67 μm caused after the ultraviolet irradiation

Effect of C60 fullerene additives on the mechanical properties of low-density polyethylene films

We have studied the effect of C60 fullerene additives on the mechanical properties (strength, Young’s modulus, elongation at break) of thin low-density polyethylene films tested for uniaxial extension.

Application of TG for valuation of selected aliphatic diamide stabilisation effect on low density polyethylene

Spontaneous structural changes of a polymer that is its ageing due to thermal energy, radiation energy, chemical compounds and micro-organisms lasting at least several season cycles change the characteristics of polymer products. Changes of polymer characteristics found during ageing can be reversible or irreversible. The most substantial changes occur as the result of UV radiation. Tests of selected aliphatic diamides of terephthalic acid as stabilisers of low density polyethylene (LD-PE) used for the production of gardening films were performed. Accelerated ageing of films for a period of one year was done in the Xenotest Alpha type apparatus. Studies were made for 0.1 mm thick commercial films. Studies of selected mechanical properties of LD-PE films without stabilisers and of LD-PE sheeting containing an addition of one of the synthesised diamides of terephthalic acid or the standard Tinuvin 783 stabiliser were performed before and after the ageing process. To determine the effect of stabilisers on the ageing process of LD-PE films, thermogravimetric analysis was applied. This allowed us to determine the decomposition activation energy of the investigated films before and after the ageing process and the influence of stabilisers on the observed changes.

Antimicrobial and Barrier Properties of LDPE Films Containing Imazalil and EDTA

Imazalil and ethylenediamine-tetraacetic acid (EDTA) were incorporated into low-density polyethylene (LDPE) aimed at producing antimicrobial packaging films for foodstuffs. Moulded plates (thickness 2mm) containing 5% of EDTA inhibited Bacillus subtilis, whereas 0.05–0.25% of imazalil had strong activity against Aspergillus niger. Further tests for antimicrobial activity, migration and oxygen and water vapor barrier properties were carried out using biaxially stretched LDPE films containing different combinations of both substances. The addition of imazalil and EDTA increased the oxygen transmission rates and water vapor permeabilities, although the effects with imazalil films were not as significant. Transparency of the EDTA containing films decreased rapidly as a function of added EDTA, whereas imazalil films were optically faultless. Total migration into 3% acetic acid and 10% ethanol was below 4 mg/dm2. Although imazalil retained its activity against A. niger on a high level (inhibition zones &gt;30 mm), the activity of EDTA was gone. None of the samples inhibited Escherichia coli.

Effects of the processing conditions and blending with linear low‐density polyethylene on the properties of low‐density polyethylene films

AbstractEffects of blending low‐density polyethylene (LDPE) with linear low‐density polyethylene (LLDPE) were studied on extrusion blown films. The tensile strength, the tear strength, the elongation at break, as well as haze showed more or less additivity between the properties of LDPE and LLDPE except in the range of 20–40% where synergistic effects were observed. The LLDPE had higher tensile strength and elongation at break than did the LDPE in both test directions, as well as higher tear strength in the transverse direction. The impact energies of the LLDPE and the LDPE were approximately the same, but the tear strength of the LLDPE was lower than that of LDPE in the machine direction. The comparative mechanical properties strongly depend on the processing conditions and structural parameters such as the molecular weight and the molecular weight distribution of both classes of materials. The LLDPE in this study had a higher molecular weight in comparison to the LDPE of the study, as implied from its lower melt flow index (MFI) in comparison to that of the LDPE. The effects of processing conditions such as the blow‐up ratio (BUR) and the draw‐down ratio (DDR) were also studied at 20/80 (LLDPE/LDPE) ratio. Tensile strength, elongation at break, and tear strength in both directions became equalized, and the impact energy decreased as the BUR and the DDR approached each other.

Effect of irradiation on the mechanical properties of low-density polyethylene films

Effect of irradiation on the mechanical properties of low-density polyethylene films