Preparation and Characterization of Low‐Density Polyethylene/Thermoplastic Starch Composites

Abstract

In this study, sago starch was physically blended with low-density polyethylene (LDPE) via the melt blending process followed by injection molding to produce LDPE/sago starch (LPS) composites. The sago starch content was varied from 5 to 30 wt% of LDPE. The addition of starch to LDPE reduced the melt flow rate (MFR), the tensile strength, and impact strength, whereas the tensile modulus, flexural strength, and flexural modulus increased. To improve poor mechanical properties of the LPS, LDPE/glycerol thermoplastic starch (LPGTS) or LDPE/2:1 mixture of glycerol and urea thermoplastic starch (LPMTS) was used in this study. The effect of compatibilizer (maleic anhydride) on properties of the LPMTS specimens was also investigated. The LPS, LPGTS, LPMTS, and maleic anhydride treated LPMTS (LPMTSM) samples were analyzed for the MFR, mechanical properties (tensile, flexural, and impact tests), thermal (TGA and DSC), and morphological properties. As a result, the incorporation of plasticizers or compatibilizer into LPS caused the considerable improvement in MFR and mechanical properties. Moreover, the presence of compatibilizer produced better properties for the LPMTSM sample than for the other samples, indicating better dispersion and homogeneity of starch to the matrix. In addition, thermal stability, DSC, and phase morphology were carried out for different LPS samples. C 2015 Wiley Periodicals, Inc. Adv Polym Technol 2016; View this article online at wileyonlinelibrary.com.

Polyethylene‐g‐starch nanoparticle biocomposites: Physicochemical properties and biodegradation studies

“…The general reduction in T m attributes to the ester linkage and incorporation of the bulky groups such as MA and NS into the chain segments of LDPE. Hence, it causes a diminution in the inbuilt granular and crystalline structures of LDPE in LMNS biocomposite [11]. The cooling thermogram indicates only slight changes in crystallization temperatures (T c ) of all samples [5].…”

“…Research is going on to the development of biodegradable LDPE by physical blending of natural renewable polysaccharides such as starch, cellulose, and chitosan with LDPE to promote microbial attack . Among natural biopolymers, starch has attracted significant attention due to its renewability, biodegradability, low cost, and high abundance .…”

“…Various studies on starch/LDPE blends and composites have revealed poor mechanical property due to the incompatibility of starch with LDPE. The least compatibility is owing to the nonpolar and polar character of hydrophobic polyethylene and hydrophilic starch, respectively [11,[15][16][17][18][19]. Compatibilizers are incorporated in starch/LDPE blends to improve its compatibility.…”

Photodegradation of low‐density polyethylene with prooxidant and photocatalyst

“…However, these biodegradable polymers are generally very expensive and have low physical, mechanical, and even processability properties which restrict the wide use of them . Another strategy is the blending of the biodegradable polymers with the polyethylene to increase the biodegradation rate of the product . But the low compatibility between these polymer and polyethylene causes to decrement of the mechanical properties of these blends and also the biodegradation zones limits to the biodegradable phases of the blends and not the PE phase .…”

Studies on electrospun poly (lactic acid) fibers and low density poly (ethylene) / thermoplastic starch blends as food packaging materials

“…It is found that different processing conditions and ratios lead to different morphologies and this affects the mechanical and barrier properties of the blends. [123][124][125][126][127] This thesis work studies the influence of morphology of PE-TPS blends using two different film forming grades of PE.…”