Effects of microcrystalline cellulose on the mechanical properties of low-density polyethylene composites

2018 ◽  
Vol 32 (3) ◽  
pp. 297-311 ◽  
Author(s):  
Yousef Ahmad Mubarak ◽  
Raghda Talal Abdulsamad

This work was intended to provide an understanding of the effect of microcrystalline cellulose (MCC) on the mechanical properties of low-density polyethylene (LDPE). The impact resistance and the tensile properties of low-density LDPE/MCC composites were investigated. The weight fraction of MCC was varied at (0, 0.5, 1, 2.5, 5, 10, 20, and 30 wt%). The obtained blends were then used to prepare the required tensile and impact testing samples by hot compression molding technique. It has been found that MCC has a strong influence on the mechanical properties of LDPE. At a low MCC weight fraction, there was a little improvement in the ultimate strength, fracture stress, and elongation at break, but at a high MCC weight fraction, the tensile properties were deteriorated and reduced significantly. The addition of 1 wt% MCC to LDPE enhanced the mentioned properties by 10, 25, and 6%, respectively. While at 30 wt% MCC, these properties were lowered by 36, 25, and 96%. The elastic modulus of LDPE composites was improved on all MCC weight fractions used in the study, at 20 wt% MCC, an increase in the elastic modulus by 12 folds was achieved. On the other hand and compared with the impact strength of pure LDPE, the addition of MCC particles enhanced the impact strength, the highest value obtained was for LDPE composites filled with 10 wt% MCC where the impact strength enhanced by two folds.

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1821
Author(s):  
Ildar I. Salakhov ◽  
Nadim M. Shaidullin ◽  
Anatoly E. Chalykh ◽  
Mikhail A. Matsko ◽  
Alexey V. Shapagin ◽  
...  

Low-temperature properties of high-density polyethylene (HDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and their blends were studied. The analyzed low-temperature mechanical properties involve the deformation resistance and impact strength characteristics. HDPE is a bimodal ethylene/1-hexene copolymer; LDPE is a branched ethylene homopolymer containing short-chain branches of different length; LLDPE is a binary ethylene/1-butene copolymer and an ethylene/1-butene/1-hexene terpolymer. The samples of copolymers and their blends were studied by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), 13С NMR spectroscopy, and dynamic mechanical analysis (DMA) using testing machines equipped with a cryochamber. It is proposed that such parameters as “relative elongation at break at −45 °C” and “Izod impact strength at −40 °C” are used instead of the ductile-to-brittle transition temperature to assess frost resistance properties because these parameters are more sensitive to deformation and impact at subzero temperatures for HDPE. LLDPE is shown to exhibit higher relative elongation at break at −45 °C and Izod impact strength at −20 ÷ 60 °C compared to those of LDPE. LLDPE terpolymer added to HDPE (at a content ≥ 25 wt.%) simultaneously increases flow properties and improves tensile properties of the blend at −45 °C. Changes in low-temperature properties as a function of molecular weight, MWD, crystallinity, and branch content were determined for HDPE, LLDPE, and their blends. The DMA data prove the resulting dependences. The reported findings allow one to understand and predict mechanical properties in the HDPE–LLDPE systems at subzero temperatures.


2021 ◽  
Vol 4 ◽  
pp. 121-126
Author(s):  
Rezza Ruzuqi ◽  
Victor Danny Waas

Composite material is a material that has a multi-phase system composed of reinforcing materials and matrix materials. Causes the composite materials to have advantages in various ways such as low density, high mechanical properties, performance comparable to metal, corrosion resistance, and easy to fabricate. In the marine and fisheries industry, composite materials made from fiber reinforcement, especially fiberglass, have proven to be very special and popular in boat construction because they have the advantage of being chemically inert (both applied in general and marine environments), light, strong, easy to print, and price competitiveness. Thus in this study, tensile and impact methods were used to determine the mechanical properties of fiberglass polymer composite materials. Each test is carried out on variations in the amount of fiberglass laminate CSM 300, CSM 450 and WR 600 and variations in weight percentage 99.5% -0.5%, 99% -1%, 98.5% -1, 5%, 98% -2% and 97.5%-2.5% have been used. The results showed that the greater the number of laminates, the greater the impact strength, which was 413,712 MPa, and the more the percentage of hardener, the greater the impact strength, which was 416,487 MPa. The results showed that the more laminate the tensile strength increased, which was 87.054 MPa, and the more the percentage of hardener, the lower the tensile strength, which was 73.921 MPa.


2013 ◽  
Vol 47 (4) ◽  
pp. 365-372 ◽  
Author(s):  
S Sultana ◽  
HP Nur ◽  
T Saha ◽  
M Saha

In this research work, cellulosic waste mango (Mangifera indica) saw dust used as the reinforcing material with low density polyethylene (LDPE). A number of samples of saw dust reinforced low density polyethylene (LDPE) composites were prepared by compression moulding technique. In order to improve the mechanical properties of saw dust-LDPE composites, unbleached raw saw dust fibers were modified by oxidation using sodium hypochlorite. FT-IR spectroscopic and scanning electron micrograph (SEM) analyses were done and the results showed the evidence of positive oxidation reaction. The effects of oxidized saw dust on the performance of oxidized saw dust reinforced LDPE composites were studied comparing with the raw saw dust-LDPE composites. The effects of fiber content on the physico-mechanical properties of composites were also studied by preparing the composites with different percentage of fiber loading (from 7.5 wt% to 30 wt%) for each type of composite. Mechanical properties such as tensile strength, tensile modulus, elongation at break, flexural strength, flexural modulus of the resulting composite were measured. Better results were obtained from oxidized saw dust-LDPE composites. Scanning electron micrograph and water absorption tests were carried out for all composites and improved results were found for oxidized saw dust-LDPE composites. Bangladesh J. Sci. Ind. Res. 47(4), 365-372, 2012 DOI: http://dx.doi.org/10.3329/bjsir.v47i4.14065


e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohammad Razavi-Nouri ◽  
Jalil Morshedian ◽  
Morteza Ehsani ◽  
Farhad Faghihi

AbstractThe tensile behavior of low density polyethylene/polydimethylsiloxane immiscible blends was investigated with respect to morphological variation of the blends. Experimental data of elastic modulus was compared with theoretical predictions of parallel model (mixing rule), as the upper bound of modulus, Halpin- Tsai model, and a two-parameter equivalent mechanical model proposed by Kolarik, which takes into account the continuity of minor phase. As the predictions of these models were not in good quantitative agreement with experiment, some modifications were made to the Kolarik model. Furthermore, a new approach for determining equivalent mechanical model parameters was proposed based on the calculation of phase continuity parameters as a function of composition. Using this approach, the values predicted for elastic modulus were found to be in good agreement with the experimental data. Moreover, the influence of a peroxide curing agent on the tensile properties of the blends was studied. The improvement of the tensile properties of the blends could have resulted from two contributions: the effect of curing reaction on the tensile properties of constituents and the better interfacial adhesion, because of possible interfacial reaction, as indicated by morphological observation.


2018 ◽  
Vol 773 ◽  
pp. 51-55
Author(s):  
Jasmine Pongkasem ◽  
Saowaroj Chuayjuljit ◽  
Phasawat Chaiwutthinan ◽  
Amnouy Larpkasemsuk ◽  
Anyaporn Boonmahitthisud

In this study, poly(lactic acid) (PLA) was melt mixed with three weight percentages (10–30wt%) of ethylene vinyl acetate copolymer (EVA) in an internal mixer, followed by a compression molding. According to a better combination of mechanical properties, the 90/10 (w/w) PLA/EVA was selected for preparing hybrid nanocomposites with three loadings (1, 3 and 5 parts per hundred of resin , phr) of poly(methyl methacrylate)-encapsulated nanosilica (PMMA-nSiO2). The nanolatex of PMMA-nSiO2 was synthesized via in situ differential microemulsion polymerization. The obtained PMMA-nSiO2 showed a core-shell morphology with nSiO2 as a core and PMMA as a shell, having an average diameter of 43.4nm. The influences of the EVA and PMMA-nSiO2 on the impact strength and the tensile properties of the PLA/EVA nanocomposites were studied and compared. It is found that the impact strength and the tensile properties of the 90/10 (w/w) PLA/EVA were improved with the appropriate amounts of the EVA and PMMA-nSiO2.


2016 ◽  
Vol 869 ◽  
pp. 326-330
Author(s):  
Julia R. Guedes ◽  
Wagner Martins Florentino ◽  
Luciano Monteiro Rodrigues ◽  
Claudinei dos Santos ◽  
Daniella Regina Mulinari

In the work, mechanical properties of palm fibers/low density polyethylene (LDPE) composites were studied. These fibers were mixed with the polymeric matrix (LDPE) in a thermokinetic mixer, in which fibers were responsible for 5 to 20 wt% in the composition. After the mixture, composites were dried, ground in mill and placed in an injector camera according to ASTM D-638 and ASTM D-790 specifications. Specimens were tested in tensile, impact, flexural and Shore A hardness mode. Results showed the addition fibers in polymeric matrix presented increase mechanical properties when compared to pure polymer


2014 ◽  
Vol 679 ◽  
pp. 154-157 ◽  
Author(s):  
Pei Ying Teoh ◽  
Abdulbaset Mohamed Erfeida ◽  
Xuan Viet Cao ◽  
Du Ngoc Uy Lan

Low density polyethylene (LDPE) and natural rubber (NR) filled silica composites were prepared by using internal mixer (Brabender) at 150°C and 50 rpm for 10 minutes. Silica was incorporated into polymer matrix by three mixing routes by using Brabender. In mixing I, filler was added into LDPE/NR blend. In mixing II, filler was added prior to LDPE, which was further compounded with NR. In mixing III, filled was pre-dispersed into NR using two-roll mill, after that the compound is blended with LDPE. The effects of filler incorporation routes on the morphological and tensile properties of prepared composites were studied. Observation from SEM result showed that silica tended to localize in NR phase than LDPE phase in the composite. In addition, silica filled LDPE/NR composite exhibited the highest tensile strength in mixing II and lowest in mixing III. Tensile fracture surface of the composites showed typical morphology of LDPE and NR phase depending on mixing methods. KEYWORDS: LDPE/NR, silica, mixing order, tensile properties, morphology


2015 ◽  
Vol 35 (8) ◽  
pp. 793-804 ◽  
Author(s):  
Md. Dalour Hossen Beg ◽  
Shaharuddin Bin Kormin ◽  
Mohd Bijarimi ◽  
Haydar U. Zaman

Abstract The aim of this research is to investigate the effects of different thermoplastic starches and starch contents on the physico-mechanical and morphological properties of new polymeric-based composites from low density polyethylene (LDPE) and thermoplastic starches. Different compositions of thermoplastic starches (5–40 wt%) and LDPE were melt blended by extrusion and injection molding. The resultant materials were characterized with respect to the following parameters, i.e., melt flow index (MFI), mechanical properties (tensile, flexural, stiffness and impact strength) and water absorption. Scanning electron microscopy (SEM) was also used in this study for evaluating blend miscibility. MFI values of all blends decreased as the starch content increased, while the sago starch formulation showed a higher MFI value than others. The incorporation of fillers into LDPE matrix resulted in an increased in tensile modulus, flexural strength, flexural modulus and slightly decreased tensile strength and impact strength. However, sago starch filled composites exhibited better mechanical properties as compared to other starches. The SEM results revealed that the miscibility of such blends is dependent on the type of starch used. The water absorption increased with immersion time and the thermoplastic sago starch samples showed the lowest percentage of water absorption compared with other thermoplastic starches.


2013 ◽  
Vol 739 ◽  
pp. 38-41
Author(s):  
Yi Chen ◽  
Yue Peng ◽  
Wen Yong Liu ◽  
Guang Sheng Zeng ◽  
Xiang Gang Li ◽  
...  

Polycarbonate/poly (lactic acid)/(PC/PLA) blend is a kind of novel potential material for introducing the degradability of PLA to high performance PC. However, the bad compatibility between PC and PLA results in poor impact resistance and strength, which limits its applications. For resolving the problem, linear low density polyethylene (LLDPE) was added into blend to improve the mechanical properties, especially the toughness. Meantime, nanosized montmorillonite was also used as an additive for modifying the blend. The results showed that the the tensile and impact strength, the elongation at break of PC/PLA all be improved with the increase of LLDPE, the nanosized montmorillonite could also increase the strength of blends when the content is lower than wt5% of blends.


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