scholarly journals Mechanical Properties of UV-Irradiated Low-Density Polyethylene Films Formulated With Carbon Black and Titanium Dioxide

2001 ◽  
Vol 24 (2) ◽  
pp. 141-150
Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 807 ◽  
Author(s):  
Lin Xia ◽  
Han Gao ◽  
Weina Bi ◽  
Wenxin Fu ◽  
Guixue Qiu ◽  
...  

Shape memory composites of trans-1,4-polyisoprene (TPI) and low-density polyethylene (LDPE) with easily achievable transition temperatures were prepared by a simple physical blending method. Carbon black (CB) was introduced to improve the mechanical properties of the TPI/LDPE composites. The mechanical, cure, thermal and shape memory properties of the TPI/LDPE/CB composites were investigated in this study. In these composites, the crosslinked network generated in both the TPI and LDPE portions acted as a fixed domain, while the crystalline regions of the TPI and LDPE portions acted as a reversible domain in shape memory behavior. We found the mechanical properties of composites were promoted significantly with an increase of CB content, accompanied with the deterioration of shape memory properties of composites. When CB dosage was 5 parts per hundred of rubber composites (phr), best shape memory property of composites was obtained with a shape fixity ratio of 95.1% and a shape recovery ratio of 95.0%.


2020 ◽  
Vol 10 (6) ◽  
pp. 771-779
Author(s):  
Jing Deng ◽  
Qi Jue Chen ◽  
Ding Jie Chen ◽  
Luo Jie Zheng ◽  
Wen Li ◽  
...  

The aim of this research was to probe the potential application of nano-titanium dioxide (TiO2)/basic magnesium hypochlorite (BMH)-containing linear low-density polyethylene (LLDPE) composite film in grape fresh-keeping. Mechanical properties, transparency, barrier performance and antibacterial activity of the nano-composite membrane were measured, and results showed that the antibacterial zone diameter of TiO2/BMH on pathogen-Aspergillus niger was 31.4 mm, with mixing ratio of BMH/TiO2 to 2:1. It was clearly shown that the synthesized nano-composite films decreased mechanical properties and transparency of the membrane, and also had a significant impact on sensory score, mass loss rate, decay rate, ascorbic acid (Vc) content and titratable acid content compared with LLDPE films. Moreover, the results revealed that the LLDPE antibacterial film can be effectively used for storing grapes, preserving the flavor of grapes and had an obviously effect in prolonging grapes’ shelf life.


2016 ◽  
Vol 705 ◽  
pp. 72-76 ◽  
Author(s):  
Reymark D. Maalihan ◽  
Bryan B. Pajarito

Polyethylene (PE) films with pro-oxidants are commonly used in agricultural and packaging industries due to their inherent biodegradability when initially expose to heat and/or light in the presence of oxygen. The degradation of films is characterized by formation of oxidation products, weight changes and loss of mechanical properties. This study investigated the relationship between tensile modulus and oxygen uptake of low-density PE films with pro-oxidants under thermal treatment at 50 and 70 °C. Blown-type films of varying colorants, thickness and pro-oxidant loading were formulated according to Taguchi design of experiments. Tensile modulus and oxygen uptake of thermally aged films were obtained from force-stroke curves and gravimetric tests, respectively. Results revealed that two out of nine formulated films showed tensile modulus to be significantly increasing with oxygen uptake at 50 °C. Correlation was more evident at 70 °C where seven out of nine formulations followed the same trend. The improvement in tensile modulus with oxygen uptake indicates increase in crystallinity of films during thermal aging. Increase in hydroxyl index of films with exposure time confirmed their degradation during heat aging. Consequently, concentration of carboxylic acids as major thermo-oxidation products was found higher at 70 °C of aging.


2018 ◽  
Vol 51 (3) ◽  
pp. 211-223
Author(s):  
M Aouinet ◽  
K Djakhdane ◽  
A Dehbi ◽  
D Castronuovo ◽  
P Picuno

The low-density polyethylene films used for greenhouse roof were naturally weathered for 9 months in harsh climatic conditions (Tiaret region, Algeria). The changes in the mechanical properties have been measured by tensile and creep-recovery tests. The measurements were carried out for both monolayer and tri-layer films. The anisotropic character of the films is preserved during ageing. The improvement in the creep resistance via cross-linking for both monolayer and tri-layer films affects different deformations. The results revealed that the degradation performance of these new tri-layer films is found to be quite better than that of the monolayer film, with regard to the mechanical properties.


2014 ◽  
Vol 895 ◽  
pp. 162-168
Author(s):  
Mohd Nasha’ain Nordin ◽  
Nik Mohd Azmi ◽  
Hasrina Hashim ◽  
Ahmad Makarimi Abdullah ◽  
Wedianti Shualdi ◽  
...  

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.


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