AA-MMA Prepolymer Grafted LLDPE as Compatibilizer for Starch-PE Blends

2011 ◽  
Vol 374-377 ◽  
pp. 170-173
Author(s):  
Li Min Tai

Through the graft copolymerization of LLDPE and the AA-MMA prepolymer by reactive extrusion on the single-screw extruder, the LLPE-g-AA-MMA was prepared and used as compatibilizer for starch/PE blends, and then the compatibilization effect was investigated. The results exhibited that the addition of this compatibilizer substantially improved the mechanical properties, especially the tensile strength. Scanning electron micrographs of the blend specimens also supported the above observations.

2012 ◽  
Vol 550-553 ◽  
pp. 1513-1521
Author(s):  
Sirirat Thothong ◽  
Klanarong Sriroth ◽  
Rattana Tantatherdtam ◽  
Amnat Jarerat

To improve the miscibility of native rice starch granules and poly(butylene adipate-co-terephthalate)(PBAT), rice starch was hydrolyzed by a mixture of α-amylase and amyloglucosidase. The obtained porous rice granular starch was then mechanically blended with PBAT by single screw extruder. Many pits and holes on the surface of starch granules were observed by scanning electron microscopy (SEM). The rough surface of the rice starch granules improved the compatibility of the polymers in the blends, which consequently increased the tensile strength and the elongation at break. In addition, SEM also revealed that the porous granules were homogeneously distributed in the polymer matrix with no appearance of gaps.


2014 ◽  
Vol 1611 ◽  
pp. 95-104 ◽  
Author(s):  
Nadira Mathura ◽  
Duncan Cree ◽  
Ryan P. Mulligan

ABSTRACTIn many tropical countries coconut (coir) fiber production is a major source of income for rural communities. The Caribbean has an abundance of coconuts but research into utilizing its by-products is limited. Environmentally friendly coir fibers are natural polymers generally discarded as waste material in this region. Research has shown that coir fiber from other parts of the world has successfully been recycled. This paper therefore investigates the mechanical properties of Caribbean coir fiber for potential applications in civil engineering.Approximately four hundred fibers were randomly taken from a coir fiber stack and subjected to retting in both distilled and saline water media. The mechanical properties of both the retted and unretted coir fibers were evaluated at weekly increments for a period of 3 months. Tensile strength test, x-ray diffraction analysis and scanning electron micrographs were used to assess trends and relationships between fiber gauge lengths, diameter, tensile strength and Young’s modulus. Diameters ranged between 0.11 mm-0.46 mm, while fiber samples were no longer than 250 mm in length. The tensile strength and strain at break decreased as the gauge length increased for both unretted and retted fibers. The opposite occurred for the relationship between the gauge length and Young’s modulus. Additionally, the tensile strength and modulus decreased as the fiber diameter increased. Neither distilled nor saline water improved the coir fiber’s crystalline index. Scanning electron micrographs qualitatively assessed fiber surfaces and captured necking and microfibril degradation at the fractured ends.The analysis revealed that the tensile strength, modulus, strain at break and crystallinity properties of the Caribbean coir fibers were comparable to commercially available coir fiber which are currently being used in many building applications.


2018 ◽  
Vol 204 ◽  
pp. 00008
Author(s):  
Heru Suryanto ◽  
Alfian Widi Rahmawan ◽  
Solichin ◽  
Sahana Rizki Tata ◽  
Uun Yanuhar

The development of materials engineering has led to many significant discoveries one of which is biocomposite with its diverse applications. The addition of reinforcing materials in biopolymers improves the composite properties. This study aimed at investigating the effect of adding nanoclay on the tensile strength, morphology, functional group, and structure of extruded biocomposites with cassava starch matrix. This experimental research involved different concentrations of nanoclay i.e. 0%, 2.5%, 5%, 7.5%. The extrusion process was performed using a single screw extruder at 120°C. The samples were characterized by tensile testing, XRD, and SEM. The biocomposite reinforced with 5% nanoclay had the highest tensile strength of 10.8 MPa. The highest diffraction peak at 2θ of 19.4° appeared in the sample added with 5% nanoclay. The addition of excessive amounts of nanoclay can hinder the formation of exfoliated structures.


2015 ◽  
Vol 1113 ◽  
pp. 99-104
Author(s):  
Mohamad Asnawi bin Ya’acob ◽  
Ku Halim Ku Hamid ◽  
Suffiyana Akhbar ◽  
Mohd Faizal Abdul Rahman

This work studies the performance of HDPE/kenaf biocomposite by varying the kenaf loading from 10 wt% to 50 wt%. Compounding has carried out by using single screw extruder. The result indicates that at 10 wt% of kenaf loading gave the highest tensile and impact strength which are25.32 MPa and 102.25 MPa respectively. Beside, at 10% to 50% of kenaf loading show increasing tensile modulus, flexural modulus and flexural strength with increment of kenaf fiber but decreasing in tensile strength and impact strength.


2011 ◽  
Vol 471-472 ◽  
pp. 898-903 ◽  
Author(s):  
Ahmad Ramli Rashidi ◽  
Uzir Wahit Mat ◽  
R.A. Abdullah

For many years, research was focused on developing a medical part of human body from polymer as to replace metal. In this study, the aim is to produce a Polyetheretherketone/Hydroxyapatite (PEEK/HA) composite which posses balance mechanical properties and good spreading of bioactive ceramic, hydroxyapatite. The composite consist of 10-30 wt% HA were compounded via nano-single screw extruder and sample for testing were produced by injection molding. Each formulation of HA was treated with (3-Aminopropyl)trimethoxysilanes coupling agent to compare with untreated HA. The result showed that the slight increasing value of Elastic modulus, flexural strength, tensile strength while decreasing flexural modulus for 10 and 20 wt% HA compared to untreated composite. The enhance of bioactivity has been proven with the incorporation of HA into PEEK. SEM-EDX image showed the bulk formation of apatite layers on the composite surface with 30 wt% HA after 3 days immersed in SBF solution. Finally, these composite be capable of being one of the biomedical part seing as the mechanical properties were found to be within the properties of human cortical and cancellous bone.


2009 ◽  
Vol 52 (6) ◽  
pp. 1505-1512 ◽  
Author(s):  
Fábio Avelino Bublitz Ferreira ◽  
Maria Victória Eiras Grossmann ◽  
Suzana Mali ◽  
Fábio Yamashita ◽  
Lisandro Pavie Cardoso

The effect of monoglyceride on microstructural, barrier and mechanical properties of casted yam starch films were investigated in different relative humidities (RH) and compared with glycerol-starch films. A single screw extruder was used to produce the starch - monoglyceride complex before film production and this process was effective to inhibit the phase separation in films. The addition of the hydrophobic compound reduced hydrophobicity, transparency and water vapor permeability of films. This later value for starch-glycerol film (1.7 x 10-10 g Pa-1 s-1 m-1) was higher than starch (1.2 x 10-10 g Pa-1 s-1 m-1) and monoglyceride-starch films (1.0 x 10-10 g Pa-1 s-1 m-1). Films containing glycerol had higher relative crystallinity (B and V H) with a slight increase at higher RH values, while for monoglyceride films, the crystallinity was constant. Monoglyceride-starch films presented poor mechanical properties when compared to glycerol- starch ones but they presented a stable behavior under different relative humidities.


2011 ◽  
Vol 221 ◽  
pp. 27-31 ◽  
Author(s):  
Rong Xian Ou ◽  
Qing Wen Wang ◽  
Fei Pin Yuan ◽  
Bao Yu Liu ◽  
Wei Jun Yang

Hydrolyzed Kevlar fibers (KFs) were compouded into high-density polyethylene (HDPE) with wood flour (WF) by twin-screw/single-screw extruder to investigate the reinforcement effects of KFs on the mechanical properties of conventional WF/HDPE composites. Maleated HDPE (MAPE) was used as a compatibilizer. The mechanical properties significantly improved as the KFs loading increases in the presence of 4% MAPE, such as tensile strength 14.7%, tensile modulus 12.4%, flexural strength 22.2%, flexural modulus 22.4%, and impact strength 41.7% with 2 wt.% KFs compared to WF/HDPE composite with MAPE. The fiber matrix morphology of the interface region in the composites was examined using scanning electron microscopy (SEM).


2012 ◽  
Vol 550-553 ◽  
pp. 1503-1512 ◽  
Author(s):  
Kamol Maikrang ◽  
Klanarong Sriroth ◽  
Kunruedee Sangseethong ◽  
Amnat Jarerat

Raw cassava starch was treated with α-amylase and amyloglucosidase in aqueous solution under annealing condition to obtain starch granules with rough and porous surfaces. Many different pits and pores formed by the activity of the enzymes on the surface granules and were observed by scanning electron microscopy (SEM). The obtained starch granules with rough surfaces were mechanically blended with poly(butylenes adipate-co-terephthalate)(PBAT) at different ratios by using a single screw extruder. The results showed that the samples comprised of enzymatically treated starch blends had higher elongation than those comprised of untreated starch blends. At 10% starch content, the treated starch/PBAT blend had about 37.55% more elongation than the untreated starch/PBAT blend. This resulted in the improved compatibility of the starch granules and PBAT matrix in the blends as confirmed by SEM.


Sign in / Sign up

Export Citation Format

Share Document