Tensile Properties and Degradability of Polyvinyl Alcohol and Starch Succinate Blend

2015 ◽  
Vol 1113 ◽  
pp. 122-126
Author(s):  
Mohd Muizz Fahimi bin Mohamed ◽  
Rahmah Mohamed

The purpose of this study was to determine the tensile properties of biodegradable Polyvinyl Alcohol (PVA) impregnated with commercial grade starch succinate (SS). PVA is a hydrophilic and hygroscopic polymer, and inclusion of SS reduces PVA's hygroscopicity and hydrophilicity. The compounding of PVA with SS was prepared by using a twin screw extruder with fixed flow modifier. The ratios of SS were varied between 5% to 20%. Melt flow index, tensile properties, soil burial and sun exposure degradability were investigated in this study. Tensile strength was observed to increase proportionate to the amount of SS incorporated while the blends were found to have greater flexibility as their elongation increases as their modulus dropped. SS was found to have greater flexibility chain which imparted greater elongation during stretching test. Higher content of SS was found to impart better degradation rate as derived from visual observation of the samples exposed to sunlight and soil burial.

2018 ◽  
Vol 773 ◽  
pp. 67-71 ◽  
Author(s):  
Paweesinee Chatkunakasem ◽  
Panisa Luangjuntawong ◽  
Aphiwat Pongwisuthiruchte ◽  
Chuanchom Aumnate ◽  
Pranut Potiyaraj

The objective of this study is to improve high density polyethylene (HDPE) properties for 3D printing by addition of graphene and low density polyethylene (LDPE). Graphene was prepared by modified Hummer’s method. The prepared graphene was characterized by the infrared spectroscopy and the X-ray diffraction analysis (XRD). Graphene/HDPE and LDPE/HDPE composites were successfully prepared through the melt-blending technique using a twin-screw extruder. The melt flow index (MFI) and differential scanning calorimetry (DSC) were employed to characterize neat HDPE and the modified HDPE. FTIR and XRD results show that graphite was successfully changed into graphene completely and MFI of graphene/HDPE and LDPE/HDPE decreased as the amount of graphene and LDPE in the composite blends increased. DSC results show that the addition of low crystalline polymers can reduce a crystallization temperature and crystallinity content.


2010 ◽  
Vol 146-147 ◽  
pp. 713-719
Author(s):  
Xia Gao ◽  
Qin Yong Mi ◽  
Wei Zhang ◽  
Zhao Hui Wang ◽  
Tong Na Mu ◽  
...  

Bisphenol A poly(carbonate) (PC) pellets used for production of 5 gallon drink water bottles were reprocessed in a twin-screw extruder for three processing cycles which simulated to those of PC bottle processing conditions. The reprocessed PC pellets were characterized by its mechanical, rheological, thermal, and optical properties. It was found that the mechanical properties of the reprocessed PC samples are slightly decreased after reprocessed. Whereas no further change was observed for the rheological and thermal properties and molecule weight of the PC samples after the second reprocessing cycles. Moreover, the melt flow index, color, and optical properties changed obviously after two reprocessing cycles.


Materials ◽  
2005 ◽  
Author(s):  
Han-Xiong Huang ◽  
Guo Jiang ◽  
Shan-Qiang Mao

Polypropylene (PP)/nano-calcium carbonate (nano-CaCO3) composite was prepared using a co-rotating, intermeshing twin-screw extruder. The effect of flow fields on the morphology of the nanocomposite was investigated. Transmission electron microscopy (TEM) was used for the determination of the morphology in the nanocomposite. The crystallization behavior of the nanocomposite was studied by using differential scanning calorimetry (DSC) and the melt shear viscosity was investigated by a melt flow index tester. The study showed that the flow field, through appropriately combining the type of the screw elements in this work, plays an important role in developing morphology of the nanocomposite. In addition, it was shown that the melt viscosity for the nanocomposite at the filler content less than 10 wt% is lower than that of neat PP.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ashwith Melkar ◽  
Ravi Kumar ◽  
Vishwa Pratap Singh ◽  
Priyanka Singh ◽  
Satyajit Samanta ◽  
...  

Abstract In the present investigation, silica and talc were used as antiblock additives with slip additive to investigate their effects on tubular quenched polypropylene (TQPP) film properties. Polypropylene (PP) powder was compounded with additives in twin-screw extruder and subsequently processed through TQPP machine to prepare the films. Tear and tensile properties [in machine direction (MD) and transverse direction (TD)] and surface properties of the produced TQPP films were investigated in terms of optics and coefficient of friction (CoF). The effect of conditioning time on CoF was also studied. Addition of slip agent alone to PP did not show any significant change in tear strength, CoF and tensile properties, whereas CoF reduced drastically by adding both slip and antiblock agents in combination. Reduction in CoF values were found to be more pronounced in the presence of silica-based antiblock compared to talc-based antiblock. Film surface morphology was further examined by field-emission scanning electron microscopy. The tear strength and the gloss of TQPP film decreased slightly in presence of only antiblock agents, but the tensile strength was found to increase. It was also found that tensile properties of TQPP films were superior in silica-based formulation, whereas tear strength was better in talc-based formulation in MD and TD.


2021 ◽  
pp. 0734242X2110570
Author(s):  
Shengwei Wang ◽  
Tao Guo ◽  
Huan Tian ◽  
Zhigang Li ◽  
Kang Fei

High-density polyethylene (HDPE) geomembranes (GMs) play a crucial role in preventing the leakage and migration of pollutants. GM service life and ageing properties are the main concerns for the choice of materials. However, it is not clear how the mechanical properties and anti-fouling performance of geomembranes change with ageing time. To solve this problem, a HDPE GM was selected for testing under exposed air condition. The tests included oxidation induction time (OIT), melt flow index (MFI), tensile properties and diffusivity under four temperature conditions for 1½ years. The test results showed that the GM has higher OIT degradation rates. Stage I – depletion of antioxidants occurred at only 10 years for the GM, which was approximately 1/4 that of the GM-GSE. The GM engineering properties index showed the same changes as those of the GM-GSE. However, MI rapidly decreased with the incubation time. The molecular weight degradation of the GM was approximately 57% and far greater than that of GM-GSE after 15 months, but the tensile properties of the two GMs showed little change. The diffusion coefficient Di of GM increases gradually with the increase of temperature in methane and trichloromethane. Under the same conditions, the diffusion coefficient Di of the GM in methane is significantly higher than that in trichloromethane, indicating that the GM has better barrier to trichloromethane.


2017 ◽  
Vol 885 ◽  
pp. 36-41 ◽  
Author(s):  
Károly Dobrovszky ◽  
Ferenc Ronkay

Blending polymers is an effective method to develop novel materials, tailoring the properties of the components. However, different morphology structures can be formed during the preparation, which could result in a wide diversity of mechanical and physical properties. The properties of polymer blends are most significantly influenced by the emerging range of phase inversion, which depends on the composition ratio and the viscosity ratio. In this paper various blends were prepared, utilizing polyethylene terephthalate (PET), polystyrene (PS) and two high density polyethylenes (HDPE), which differ in flowability. After preliminary homogenization by twin screw extruder, standard injection moulded specimen were prepared in order to present the effects of phase inversion on tensile properties, shrinkage and burning characteristics in binary polymer blends.


2013 ◽  
Vol 747 ◽  
pp. 673-677 ◽  
Author(s):  
Worasak Phetwarotai ◽  
Duangdao Aht-Ong

Biodegradable ternary blend films of nucleated polylactide (PLA), poly (butylene adipate-co-terephthalate) (PBAT), and thermoplastic starch (TPS) with the presence of nucleating agent and compatibilizer were prepared via a twin screw extruder. The effects of compatibilizer types and starch contents on the thermal, morphological, and tensile properties of these blend films were evaluated. Two types of compatibilizer (methylene diphenyldiisocyanate (MDI) and polylactide-graft-maleic anhydride (PLA-g-MA)) were used for enhancing an interfacial adhesion of the blends, whereas TPS from tapioca starch was added as a filler at various concentrations (0 to 40 wt%). In addition, talc and PBAT acted as a nucleating agent and a flexible polymer were fixed at 1 phr and 10 wt%, respectively. The results indicated that the thermal stability of the blend films was affected from the presence of compatibilizer and TPS. In addition, the tensile properties and compatibility of PLA, PBAT, and TPS blends were improved with the addition of compatibilizer compared to uncompatibilized blend films as evidenced by SEM results. Furthermore, the blend films with MDI gave higher mechanical properties than those with PLA-g-MA at all compositions. The water absorption of the ternary blend films was evidently increased when the TPS amount was increased; in contrast, tensile strength and elongation at break (EB) of these blend films were significantly decreased.


2017 ◽  
Vol 264 ◽  
pp. 120-123 ◽  
Author(s):  
Sung Ting Sam ◽  
Omar Sabbar Dahham ◽  
Pei Gie Gan ◽  
N.Z. Noimam ◽  
Jingi Y. Kuan ◽  
...  

Currently, natural fillers seem to be the suitable materials in polymer industry, which have emerged as a viable and abundant replacement for the relatively high-cost and non-renewable conventional fillers. However, the direct introduction of natural fillers into polymer matrix could effect negatively on some properties. Therefore, the aim of this work is to evaluate the influence of jackfruit seed flour (JFSF) (before and after compatibilization) on the tensile properties of (LDPE/JFSF) blends. Different JFSF content (5, 10, 15 and 20 wt.%) with (63-100 𝜇𝑚) particle size were prepared in this work. Twin-screw extruder at 150°C and 50rpm screw speed followed by hot-compress machine at 150°C and 10MPa pressure were used respectively to produce (LDPE/JFSF) blends. Adipic acid (AA) solution was added as a compatibilizer into all blends equally (25wt% AA into 75wt% JFSf). The changes of tensile and morphological properties were investigated. Results shown decreasing on tensile strength and elongation at break of LDPE/JFSF and LDPE/JFSF/AA as JFSF increased. In contrast, Young’s modulus increased up to 10 wt.% of JFSF and then decreased. However, the addition of Adipic acid, particularly for JFSF 5wt.% has improved the tensile properties of LDPE/JFSF blends. The SEM micrographs showed the agglomeration at high JFSF content (20 wt%) which in turn effected negatively on the tensile properties. However, the blends show homogeneous surfaces as AA added.


2019 ◽  
pp. 089270571986462 ◽  
Author(s):  
Rupinder Singh ◽  
Ranvijay Kumar ◽  
Shubham Tiwari ◽  
Shubham Vishwakarma ◽  
Shivam Kakkar ◽  
...  

In this study, an innovative route for secondary recycling (with zirconium oxide (ZrO2) reinforcement) has been proposed based on melt processing of high-density polyethylene (HDPE) in low-temperature bearing applications. Initially, secondary recycled HDPE, acrylonitrile butadiene styrene, and nylon 6 thermoplastic composites were investigated for melt flow index (MFI) according to ASTM D1238 standard. Based on the acceptable MFI, secondary recycled HDPE matrix was selected for second-stage processing on twin screw extrusion (TSE). The final process involves reinforcement of ZrO2 into HDPE matrix by TSE in 60:40 ratio (by weight %) for preparation of feedstock filament (for possible 3-D printing of bearings). The results of the study suggest that for processing of HDPE, 40% ZrO2 composite matrix, 50 r min−1 screw speed, 190°C barrel temperature, and 15 kg applied load are the best setting of TSE (for maximizing the tensile strength of feedstock filament). The results are also supported by wear properties, thermal stability, and morphological analysis (based on scanning electron microscopy and electron-dispersive X-ray analysis).


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