Weiwei Duan^*, Lingfeng Tang

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1143-1164, 2021, DOI:10.32604/fdmp.2021.016692 - 08 September 2021

Abstract Vertical infusion (self-emptying) bags used for Intravenous infusion are typically obtained by moulding a soft envelope of polypropylene. In normal conditions a continuous flow of liquid can be obtained with no need to use a pump. In the present study, the relationship between air pressure effects and the drug drip rate have been investigated experimentally and numerically. After determining relevant experimental data about the descending height of liquid level, the dropping speed and pressure, the ordinary least square method and MATLAB have been used to reconstruct the related variation and interrelation laws. Numerical simulations have More >

Zhiyu Weng¹, Lina Wang^1,2,*, Qiang Liu², Xuemin Pan¹, Yonghao Xu³, Jing Li¹

Journal of Renewable Materials, Vol.9, No.8, pp. 1503-1517, 2021, DOI:10.32604/jrm.2021.015003 - 08 April 2021

Abstract To explore an environmentally friendly improvement measure for red clay, the function and mechanism of xanthan gum biopolymer and polypropylene fibers on the strength properties of red clay were investigated by unconfined compressive strength and scanning electron microscopy tests. The test results demonstrated that the contents and curing ages of xanthan gum had significant influences on the unconfined compressive strength of red clay. Compared with untreated soil, 1.5% xanthan gum content was the optimal ratio in which the strength increment was between 41.52 kPa and 64.73 kPa. On the other hand, the strength of xanthan… More >

Mateusz Barczewski^1,*, Jacek Andrzejewski^1,*, Radomir Majchrowski², Kamil Dobrzycki¹, Krzysztof Formela³

Journal of Renewable Materials, Vol.9, No.5, pp. 841-853, 2021, DOI:10.32604/jrm.2021.014490 - 20 February 2021

Abstract Agricultural waste is a still untapped source of materials that can, in case of proper utilization, significantly improve the sustainability of polymers and their composites. In this work, polymer composites based on isotactic polypropylene were produced incorporating ground sunflower husk in the amount of 10 wt% and 20 wt%. The work’s main objective is to evaluate how preliminary fractioning of this agricultural waste filler affects the thermomechanical properties, microstructure and surface topology of polypropylene-based injection molded composites. The composites were analyzed for mechanical properties (tensile, impact strength and hardness), thermomechanical properties (Vicat softening point VST,… More >

Alexandra Augusta Reichert¹, Mariana Ribas de Sá², Gabriela Escobar Hochmuller da Silva¹, Cesar Augusto Gonçalves Beatrice³, André Ricardo Fajardo⁴, Amanda Dantas de Oliveira^1,*

Journal of Renewable Materials, Vol.8, No.10, pp. 1327-1341, 2020, DOI:10.32604/jrm.2020.010291 - 31 August 2020

Abstract Nowadays, the production of consumer goods is based on the use of non-renewable raw materials, which in recent years has been performing as a problem for the environment. Considering the large number of available biofibers in nature, their use in the development of polymeric composites has inevitably emerged, it is also necessary to take into account the countless discarded plastics that still have the potential to be reused. In this work, fibers were extracted from pineapple crown residues and utilized to compose sustainable composites using recycled polypropylene from cups discarded in the trash as a… More >

RAVI KUMAR, VISHWA PRATAP SINGH, MADHUKAR PRAJAPATI, ASHWITH, PRIYANKA SINGH, SATYAJIT SAMANTA, SAIKAT BANERJEE^*

Journal of Polymer Materials, Vol.36, No.4, pp. 323-335, 2019, DOI:10.32381/JPM.2019.36.04.3

Abstract Types of nucleating agents and their dosage level play an important role on the crystallinity of the polymer which controls the final properties like optical clarity, stiffness and reduced cycle time during molding. In this study, the efficiency of two different types of commercially available nucleating agents, phosphate ester and dicarboxylic acid based, have been studied. Both the nucleating agents were compounded with molding grade polypropylene homopolymer having melt flow index (MFI) of 12 g/10min at 2.16 Kg and 230°C, in a co-rotating twin screw extruder at two different dosage level, i.e. 300 ppm and… More >

XIAOYAN LIU^a,*, XU CHEN^a, HONGXING ZHANG^b, CHANGJUN ZHANG^a, SHIYUAN YANG^a, GUANGQUAN LI^a

Journal of Polymer Materials, Vol.36, No.2, pp. 121-132, 2019, DOI:10.32381/JPM.2019.36.02.2

Abstract In this work, three in situ impact polypropylene copolymer(IPC) samples were prepared through Ziegler-Natta catalyst only changing the feed composition (ethylene to ethylene and propylene molar ratio, C2/C2+C3) in gas-phase polymerization reactor. Polymer (IPC) were characterical by solvent classification, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), successive self-nucleation and annealing (SSA), nuclear magnetic resonance(13C-NMR) and scanning electron microscopy(SEM). The mechanical properties of IPC samples were tested.The results indicate that with similar ethylene content, the feed composition which determines the content and structure of EPR and EbP component in IPC, further impacts the rubber phase More >

Joyce de P. Cipriano², N. C. Zanini¹, I. R. Dantas¹, D. R. Mulinari^1,*

Journal of Renewable Materials, Vol.7, No.10, pp. 1047-1053, 2019, DOI:10.32604/jrm.2019.00001

Abstract The use of natural fibers as an additive in polymeric matrices has attracted interest of the automotive industries, for its low cost, mechanical properties, biodegradability and lightness. However, the hydrophilic nature of the fiber makes polymer compatibility difficult. Fiber surface treatments can be used to enhance the fiber/matrix interface. In the present work, polypropylene (PP) composites reinforced with fibers from macadamia nutshell were obtained and characterized. Macadamia nutshell fibers were treated by an alkaline treatment with sodium hydroxide (NaOH 4%) to improve adhesion between fibers and matrix. Fibers were characterized by techniques of Scanning Electron More >

Fatima Ezzahra El Abbassi^1,*, Mustapha Assarar², Rezak Ayad², Hamid Sabhi², Stephane Buet², Nouzha Lamdouar³

Journal of Renewable Materials, Vol.7, No.3, pp. 253-267, 2019, DOI:10.32604/jrm.2019.01759 - 14 July 2021

Abstract This paper aims at studying the effect of recycling on the static and dynamic properties of short alfa fibre reinforced polypropylene. For this purpose, alfa fibres reinforced composites were elaborated by an injection moulding process and were subjected to different mechanical recycling cycles. Then, non-recycled and recycled materials were subjected to static tests and Dynamic Mechanical Analysis (DMA) to evaluate the effect of recycling on their behaviour. Besides, the effects of alkali and salt water treatments on the static and dynamic properties of the alfa composite were also investigated. The obtained results show that tensile More >

Estela Krause Sammartino^1,2,3†, María Marta Reboredo⁴, Mirta I. Aranguren^*,4

Journal of Renewable Materials, Vol.4, No.2, pp. 101-112, 2016, DOI:10.7569/JRM.2014.634144

Abstract Composites made from polypropylene (PP) and local South American fibers traditionally used in yarnderived craftsmanships, Caranday Palm, were studied regarding the effect of fiber addition, concentration and characteristics of the coupling agent (molecular weight and percentage of grafted maleic anhydride), as well as type of processing. A laboratory-scale intensive mixing followed by compression, and pilot plant twin extrusion followed by injection, were the two processes investigated. The use of the first one allowed the selection of processable formulations with high fiber concentration and a percentage of coupling agent below the surface fiber saturation. In fact,… More >

Xiaoqing Zhang^*, Simon Schmidt^φ, Nick Rigopoulos, Januar Gotama, Eustathios Petinakis

Journal of Renewable Materials, Vol.3, No.2, pp. 91-100, 2015, DOI:10.7569/JRM.2014.634135

Abstract The behavior of a biodegradable CO₂ -based polymer polypropylene carbonate (PPC) as polymer matrix of wood fi ber (WF) composites was examined and compared with that of using poly(lactic acid) (PLA) as the matrix. The PPC/WF composites displayed poor mechanical properties as compared to PLA/WF composites because PPC is an amorphous polymer with low T_g and poor thermal stability. However, when PPC was used in conjunction with PLA in WF composites, the mechanical strength and modulus of the composites could match or even exceed the level of PLA/WF composites. The strong intermolecular interactions between PPC and More >