Effect of Alkali Treatment on Surface Morphology and Properties of Jute Yarns

2011 ◽  
Vol 264-265 ◽  
pp. 1922-1927 ◽  
Author(s):  
S.K. Shaha ◽  
S. Dyuti ◽  
Qumrul Ahsan ◽  
Mahbub Hasan

Due to the environmental issue, natural fibers are day by day becoming attractive to researchers. Natural fiber contains cellulose, hemicelluloses, lignin etc, which are hygroscopic in nature and biodegradable. The lack of surface feature diminishes its properties. So, the surface properties of the jute yarns need to be modified. In the present study, jute yarns were cleaned using 2% detergent and chemically modified by 5, 15 and 25% NaOH solution both at room temperature and 700C for 2 hours and dried in air. The structural and morphological studies of the treated and untreated yarns were carried out using Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM). The thermal and mechanical behaviour of the yarns were analyzed using Differential scanning calorimetry (DSC) and Instron Universal testing machine. The results show the improvement in mechanical strength of the yarns due to the change in crystalinity after alkali treatment. Also, the thermal decomposition temperature of raw jute yarns decreased from 357.30C to 349.60 C after alkali treatment.

2018 ◽  
Vol 159 ◽  
pp. 02005 ◽  
Author(s):  
Herald Kurnia Adi ◽  
Fauzia Hanum Ikhwan ◽  
Hasyim Aidilichsan Muliawan ◽  
Mochamad Chalid

Polyurethanes are one of many types of polymers that are currently being developed worldwide. Some studies reported many substances involved in synthesizing polyurethanes (PU), with mostly originated from a biomass substance. Our laboratory has synthesized natural fiber – based PU to obtain hybrid PUs through varying reaction variables such as temperature. This study used cellulose, a biomass substance as well as polyethylene glycol and 4,4’ – methylenebis cyclohexyl isocyanate (HMDI) in synthesizing the hybrid PU, and investigated their thermal stability such as decomposition temperature by Differential Scanning Calorimetry (DSC) showed various tendency according to the chain extending temperature for the decomposition temperature. Simultaneous Thermal Analysis (STA) showed glass transition tendency of the product is proportional to the chain extending temperature, where the maximum glass transition obtained from the experimental is 59.8ºC at 70ºC of polymerization. Evaluation of functional group in the hybrid PUs was conducted with FT – IR spectroscopy measurement indicating urethane presence as part of the hybrid PUs.


2011 ◽  
Vol 415-417 ◽  
pp. 666-670 ◽  
Author(s):  
Na Lu ◽  
Shubhashini Oza ◽  
Ian Ferguson

Natural fiber reinforced composites are being used as reinforcement material in composite system due to their positive environmental benefits. Added to that, natural fibers offer advantages such as low density, low cost, good toughness, high specific strength, relatively non-abrasive and wide availability. However, the low thermal stability of natural fibers is one of the major challenges to increase their use as reinforcing component. In this study, a thorough investigation has been done to compare the effect of two chemical treatment methods on the thermal stability of hemp fibers. 5wt% sodium hydroxide and 5wt% triethoxyvinylsilane was used for the treatment of hemp fibers. Fourier transform infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis were used for characterization of untreated and treated fiber. The results indicated that 24 hours alkali treatment and 3 hours silane treatment time enhanced the thermal stability of the hemp fiber. However, alkali treatment shows better improvement compared to silane treatment.


2020 ◽  
Vol 29 ◽  
pp. 84-92
Author(s):  
Md. Sahadat Hossain ◽  
Mashrafi Bin Mobarak ◽  
Farzana Khan Rony ◽  
Sazia Sultana ◽  
Monika Mahmud ◽  
...  

Concerning the importance of composite material for multi-purpose applications, an attempt has been taken to synthesize composites using natural fiber with unsaturated polyester resin. Since the use of synthetic polymer plays a key role in polluting the environment, we have used natural fiber (banana fiber) as an alternative source. Our approach dealt with the preparation of reinforced composites by hand lay-up technique using 20 % banana fiber (by weight) as reinforcing materials. Several techniques were applied to characterize synthesized composites e.g. universal testing machine (UTM), Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM). UTM facilitated the measurement of the tensile strength (TS), tensile modulus (TM), elongation at break (EB), bending strength (BS), and bending modulus (BM) while functional groups were confirmed by FT-IR and the morphology of the composites was investigated by SEM. Observed results revealed that the TS, TM, BS, and BM followed an increasing fashion of 100%, 53%, 75%, and 55% respectively with respect to the matrix materials. On the other hand, the EB of the composite reduced drastically by 50%. Hence, higher mechanical properties were obtained for the banana fiber reinforced composites (BFRC) than the unsaturated polyester resin (UPR) matrix.


2019 ◽  
Vol 130 ◽  
pp. 01018
Author(s):  
Juliana Anggono ◽  
Hariyati Purwaningsih ◽  
Suwandi Sugondo ◽  
Steven Henrico ◽  
Sanjaya Sewucipto ◽  
...  

Greater interest in recent years to the increase demand in using natural fiber reinforcement of polymers is to comply with the increasing stringent international protocols related to climate change and environmental awareness. Many studies have reported the development of renewable and biodegradable agricultural by-products as reinforcement fibers for biocomposites. One of the essential factors in producing strong biocomposites is the properties prepared from the natural fibers which results from the alkalitreatment given. This research aims to evaluate the effect of different treatment duration on structural changes on sugarcane after alkali treatment using sodium hydroxide (NaOH) and calcium hydroxide (Ca(OH)2) solutions. Calcium hydroxide was used as comparative solution in search for milder and more environmental friendly alkali solution as an alternative solution of NaOH. Fourier Transform Infrared (FTIR) confirmed the major removal of lignin and minor of hemicellulose. It shows that the structure did not change considerably with the additional treatment time. The weight loss measurement after each treatmentshows a higher weight loss with the treatment with NaOH (40.5 % to 57.75 %) than the weight loss after Ca(OH)2 treatment (25 % to 46 %). Scanning electron microscope (SEM) observed the morphology changes onthe fiber from both treatments.


Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 484 ◽  
Author(s):  
Stefan Cichosz ◽  
Anna Masek

When considering cellulose (UFC100) modification, most of the processes employ various solvents in the role of the reaction environment. The following article addresses a solvent-free method, thermal drying, which causes a moisture content decrease in cellulose fibers. Herein, the moisture content in UFC100 was analyzed with spectroscopic methods, thermogravimetric analysis, and differential scanning calorimetry. During water desorption, a moisture content drop from approximately 6% to 1% was evidenced. Moreover, drying may bring about a specific variation in cellulose’s chemical structure. These changes affected the cellulose-filled polymer composite’s properties, e.g., an increase in tensile strength from 17 MPa for the not-dried UFC100 to approximately 30 MPa (dried cellulose; 24 h, 100 °C) was observed. Furthermore, the obtained tensile test results were in good correspondence with Payne effect values, which changed from 0.82 MPa (not-dried UFC100) to 1.21 MPa (dried fibers). This raise proves the reinforcing nature of dried UFC100, as the Payne effect is dependent on the filler structure’s development within a polymer matrix. This finding paves new opportunities for natural fiber applications in polymer composites by enabling a solvent-free and efficient cellulose modification approach that fulfils the sustainable development rules.


2016 ◽  
Vol 36 (3) ◽  
pp. 245-252 ◽  
Author(s):  
Samira Sahi ◽  
Hocine Djidjelli ◽  
Amar Boukerrou

Abstract This paper illustrates the aim to introduce biodegradable vegetable filler in synthetic polymers to prepare novel biodegradable composites. Low density polyethylene/alkali treated corn flour (LDPE/ATCF) composites were prepared by reactive extrusion using a twin-screw extruder. The microstructure, thermal properties and tensile properties were evaluated and compared with virgin LDPE. The Fourier transform infrared (FTIR) spectra showed a decrease in the hydrophilic nature of corn flour (CF) after alkali treatment. Scanning electron microscopy (SEM) micrographs showed good dispersion between matrix and filler. The tensile and elongation at break decreased by increasing the filler content in the composites. However, the Young’s modulus increased with the increase in filler content. The biodegradation of composites was studied in the environment using the soil burial test for 6 months. Differential scanning calorimetry (DSC) analysis showed an increase of the melting enthalpy (ΔHm) and crystallinity of LDPE with evidence of degradation. The biodegradability of the composites was enhanced with increasing ATCF content in the matrix. This result was supported by weight loss and degraded surface of composites observed through morphological studies. From the results, we conclude that the use of ATCF as filler in LDPE reduces pollution problems. This is advantageous for both the economy and the environment.


2016 ◽  
Vol 847 ◽  
pp. 241-248 ◽  
Author(s):  
Ya Juan Wang ◽  
Ya Li ◽  
Xin Zhang ◽  
Ning Kun Wu ◽  
Shuang Xi Shao

In order to reduce the pollution of the waste material, the waste leather powder tanned with vegetable tannin was used in this work, and vinyitrimethoxy silane was chosen as coupling agent. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to investigate the thermal properties of the powder sample. Both thermal decomposition temperature and denaturation temperature of the modified sample were higher than those of the raw samples due to the interaction between leather powder and silane, which can be demonstrated by Scanning Electron Microscopy-Energy Dispersive Spectrometer (SEM-EDS) and Fourier Transform Infrared Spectroscopy (FT-IR). Additionally, the flowing property, hydrophilicity and water absorption rate of the powder samples was also examined. The results showed that the hydrophilicity and moisture absorption of the leather powder sample modified with silane was lower than the raw materials. And the flowing properties of the modified samples also decreased because of the coupling reaction of the flexible vinyitrimethoxy silane.


2017 ◽  
Vol 894 ◽  
pp. 50-55
Author(s):  
Leslie Joy L. Diaz ◽  
Stella Marie Hagad ◽  
Peter June M. Santiago

Properties of composite materials are often predicted from properties of its component materials. In the case of green composites that are typically filled with natural fibers however, a large deviation from predictions is observed due to the large property variation in natural fibers. In this study, techniques have been developed to minimize the effect of the said variations, which included the determination of a fiber useful length and critical length, and the utilization of controlled chemical treatment to remove unwanted fiber components that interfere in fiber-matrix interfacial bonding. The abaca fiber was determined to have a diameter of 190 + 2 mm in about two-thirds of the fiber length in the middle section. A large variation in fiber diameter was observed at the root and tip sections such that the diameter could be as high as 200 mm at the root while the tip tapers to 110 to 165 mm. The useful length with constant diameter was determined to be about 2000 mm at the middle section. The critical length of this useful length was found to be 3.15 mm. The tensile strength was also determined to have an average of 970 MPa when measured at 15 mm gauge lengths but is found to decrease up to 796 MPa with increasing gauge lengths up to 35 mm. This superior tensile strength of abaca is also associated to the 2-3o microfibril misorientation from the axis of the fiber. Use of the fibers in composite as continuous and unidirectional filler at 5% loading to unsaturated polyester (tensile strength of 40 MPa) resulted to a tensile strength of 48 MPa. The tensile strength increased to 71 MPa when chemically treated continuous fiber was employed. Alkali treatment at relatively high temperature improved the surface morphology of the fiber, with waxes and lignin removed from the surface and activating the surface with hydroxyl functional groups, that essentially improved the wettability of the polymer to the fiber, and densified the fiber with the closure of its lumens.


2020 ◽  
Vol 6 (1) ◽  
pp. 76
Author(s):  
Adhi Setiawan

The use of natural fiber as reinforcement for epoxy polymer composites is currently a concern for researchers because it is environmentally friendly so it can replace glass fiber or carbon in engineering applications. Palm fiber is a type of natural fiber that is produced by the cooking oil industry as a component of waste. The surface modification of fiber with NaOH solution is one of the factors that determines level of adhesion to the epoxy polymer matrix. This study to analyze the effect of alkali treatment on the morphology and characteristics of fiber. In addition, the effect of palm fiber composition on the mechanical properties of composites were studied. Alkali treatment on fiber was carried out using 10% wt sodium hidroxide solution. The morphology and characteristics palm fiber before and after alkali treatment were analyzed using SEM-EDX, XRD, and FTIR. Tensile tests were carried out on composites with treated fibers and without treatment with sodium hidroxide solution. The results showed that alkali treatment caused the surface morphology of the fiber to be finer due to the loss of lignin and hemicellulose components. Alkali treatment fiber can increase the tensile strenght. Composites with fiber and resin composition of 4%: 96% wt that have undergone alkali treatment have a maximum tensile strength of 21.60 MPa.


2020 ◽  
pp. 325-327
Author(s):  
Sumesh K R ◽  
Kanthavel K ◽  
Saikrishnan G

The applications of natural fiber composites have enormously increased due to the high availability, eco-friendly nature and practical applications of the composites. In this review different fiber combinations using natural fiber and synthetic fibers have been investigated and found with interesting results. The hybrid nature of fiber reinforcement adds to the mechanical properties of polymer-based composites. The hybridization using more than one fiber reduces the surface deformations in the polymer matrix and enhanced the bonding ability of polymer composites. The alkali treatment was the effective surface treatment process for improving the cellulosic nature with good crystalline nature, good bonding ability with the polymer matrix, this adds to the properties of polymer-based composites. The crystallinity index of 43-68 % were observed in surface treated natural fibers.


Sign in / Sign up

Export Citation Format

Share Document