scholarly journals Effect of temperature and moisture content on tensile behaviour of false banana fibre (Ensete ventricosum)

2017 ◽  
Vol 31 (3) ◽  
pp. 377-382 ◽  
Author(s):  
Cestmir Mizera ◽  
David Herak ◽  
Petr Hrabe ◽  
Abraham Kabutey

Abstract The mechanical behaviour of natural fibres as composite materials can be affected by changes in temperature and moisture content. The aim of this paper was to describe the effect of temperature and moisture content on tensile strength of false banana fibre (Ensete ventricosum) and to determine its water absorption. Samples of fibres were prepared and tested until rupture point with strain rate of 0.05 min−1 at temperature change between −20 and 220°C as well as moisture content between 10 and 90% wb. The water absorption and release of Ensete fibres at 60 and 90% relative humidity was also determined. Results showed that Ensete fibres exhibited stability of tensile strength in the temperature range from 0 to 100°C but the increase of temperature decreased statistically significantly the tensile strength. The effect of moisture content on tensile strength was not statistically significant. The equilibrium moisture content at 60% relative humidity and 25°C was determined.

2016 ◽  
Vol 47 (2) ◽  
pp. 90-96 ◽  
Author(s):  
Č. Mizera ◽  
D. Herák ◽  
P. Hrabě ◽  
M. Müller ◽  
A. Kabutey

Abstract The effect of gauge length of false banana fibre (Ensete ventricosum) on the tensile strength, volume energy, and modulus of elasticity under tensile loading was examined. Fibres of gauge length L0 (mm) 10, 20, 40, 80, 160, and 320 mm were prepared and tested until rupture point at strain rate of 0.05 min−1. Mathematical models describing the mechanical behaviour of the varying gauge lengths were presented. With the increasing gauge length of fibre, the tensile strength and volume energy decreased while the values of modulus of elasticity increased. The theoretical model describing the mechanical behaviour of Ensete fibre under tensile loading presented herein provides useful information for the fibres application in industry. The determined models could be used as a background for further research focused on Ensete fibre application.


Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3487
Author(s):  
Walid Abotbina ◽  
S. M. Sapuan ◽  
M. T. H. Sultan ◽  
M. F. M. Alkbir ◽  
R. A. Ilyas

This work aims to develop cornstarch (CS) based films using fructose (F), glycerol (G), and their combination (FG) as plasticizers with different ratios for food packaging applications. The findings showed that F-plasticized film had the lowest moisture content, highest crystallinity among all films, and exhibited the highest tensile strength and thermostability. In contrast, G-plasticized films showed the lowest density and water absorption with less crystallinity compared to the control and the other plasticized film. In addition, SEM results indicated that FG-plasticized films had a relatively smoother and more coherent surface among the tested films. The findings have also shown that varying the concentration of the plasticizers significantly affected the different properties of the plasticized films. Therefore, the selection of a suitable plasticizer at an appropriate concentration may significantly optimize film properties to promote the utilization of CS films for food packaging applications.


2007 ◽  
Vol 70 (1) ◽  
pp. 164-171 ◽  
Author(s):  
HECTOR A. PALACIOS-CABRERA ◽  
HILARY C. MENEZES ◽  
BEATRIZ T. IAMANAKA ◽  
FREDERICO CANEPA ◽  
ALDIR A. TEIXEIRA ◽  
...  

Changes in temperature, relative humidity, and moisture content of green coffee beans were monitored during transportation of coffee from Brazil to Italy. Six containers (three conventional and three prototype) were stowed in three different places (hold, first floor, and deck) on the ship. Each prototype was located next to a conventional container. The moisture content of the coffee in the container located on the first floor was less affected by environmental variations (0.7%) than that in the hold and on the deck. Coffee located in the hold showed the highest variation in moisture content (3%); in addition, the container showed visible condensation. Coffee transported on the deck showed an intermediary variation in moisture (2%), and there was no visible condensation. The variation in coffee moisture content of the prototype containers was similar to that of the conventional ones, especially in the top layers of coffee bags (2 to 3%), while the increase in water activity was 0.70. This suggests that diffusion of moisture occurs very slowly inside the cargo and that there are thus sufficient time and conditions for fungal growth. The regions of the container near the wall and ceiling are susceptible to condensation since they are close to the headspace with its high relative humidity. Ochratoxin A production occurred in coffee located at the top of the container on the deck and in the wet bags from the hold (those found to be wet on opening the containers at the final destination).


2012 ◽  
Vol 576 ◽  
pp. 289-292 ◽  
Author(s):  
Ahmad Zuraida ◽  
A.R. Nur Humairah ◽  
A.W. Nur Izwah ◽  
Z. Siti Naqiah

Thermoplastic sago starch (TPSS) was produced by plasticizing with glycerol through melt blending before being compression moulded. The investigated TPSS was prepared at glycerol/starch weight fraction of 40/60, 35/65 and 30/70. The functional groups composition, tensile strength, density, moisture content and water absorption were evaluated and compared at different glycerol/starch ratio. The compatibility of the glycerol as the plasticizer in the TPSS was proven by Fourier transform infrared spectroscopy (FTIR) where glycerol could form stable hydrogen bond with sago starch. This preliminary study demonstrated that the stress at maximum load was only applicable for lower glycerol/starch ratio of 30/70. The density of TPSS was inversely proportional to the increment of glycerol/starch ratio whereas moisture content and water absorption had opposite relationship.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Manuel Fernando Coronado Jorge ◽  
Elisabete M. C. Alexandre ◽  
Christian Humberto Caicedo Flaker ◽  
Ana Mônica Quinta Barbosa Bittante ◽  
Paulo José do Amaral Sobral

The main objective of this research was to study the properties of gelatin-based nanocomposites reinforced with the montmorillonite (MMT). The gelatin-based nanocomposites were prepared with solutions of 5 g of gelatin/100 g of film-forming solution, 0–10 g of montmorillonite/100 g of gelatin, and 30 g of glycerol/100 g of gelatin and were stored for 7 days at 58% relative humidity or in silica gel, depending on the type of assay. The reinforcement of gelatin-based nanocomposites with montmorillonite increased their thickness and decreased the moisture content. Tensile strength and Young’s modulus increased revealing more resistant and rigid nanocomposites. The increase in MMT concentration slightly changed the X-ray diffraction spectra indicating some loss of crystallinity and reinforced films presented less homogeneous structures. The montmorillonite concentration had not a clear effect on the thermal properties and FTIR spectra of nanocomposites were very similar to separated compounds.


2020 ◽  
Vol 8 (3) ◽  
pp. 329
Author(s):  
Liza Natasya Pongmassangka ◽  
Bambang Admadi Harsojuwono ◽  
Sri Mulyani

This study aims to determine the effect of temperature regulation and the appropriate drying time on the manufacture of bioplastic composites of maize and glucomannan mixtures, as well as providing information on science and technology in the field of bioplastics. This experimental design uses the complete random design method. The first factor is the drying temperature of bioplastic composites from a mixture of cornstarch and glucomannan which consists of 3 levels, namely 60 ± 1; 65 ± 1; 70 ± 1 ° C. Factor 2 is the drying time which consists of 3 levels, namely for 16, 17.5 and 19 hours. The variables observed were tensile strength, elongation at break, elasticity, swelling and biodegradation. Data were analyzed for diversity and continued with the Tukey test to find out the difference of design experiment. The results showed that temperature and drying time and their interactions had a very significant effect on tensile strength, elongation, elasticity, and water absorption. but the temperature treatment and interaction have no significant effect on the ability of biodegradation. The interaction between treatments has a very significant effect on elongation, elasticity and water absorption. and has a significant effect on tensile strength. The best biodegradable plastic characteristics were determined by tensile strength test at a temperature of 70 °C with 16 hours drying time which resulted in tensile strength values ??of 2,395MPa. Bioplastics produced in this study did not meet the criteria of mechanical tensile strength, elasticity and thickness development. Keywords: Bioplastics, glycerol, glucomannan and maizena.


1970 ◽  
Vol 43 (4) ◽  
pp. 581-587
Author(s):  
M Hasan Shahria ◽  
M Ashaduzzaman ◽  
M Iftekhar Shams ◽  
Arifa Sharmin ◽  
M Muktarul Islam

The study was conducted to find out the potentiality of Pitali (Trewia nudiflora) for manufacturing commercial plywood and evaluating its physical and mechanical properties. Two 9-ply plywood of 2.4m x 1.2m x 18mm size were manufactured using liquid urea formaldehyde adhesive. The physical and mechanical properties of T. nudiflora plywood were compared with the existing market available plywood manufactured by Simul (Bombax ceiba). It was found that density were 509.82 kg/m3 and 490.96 kg/m3, moisture content after curing were 10.67% and 17.61%, thickness swelling were 6.90% and 7.29%, linear expansion were 0.19% and 0.15%, water absorption were 50.89% and 64.79%, MOR were 29.94 N/mm2 and 27.05 N/mm2, MOE were 1613.89 N/mm2 and 1160.68 N/mm2, and tensile strength were 14.75 N/mm2 and 13.12 N/mm2 for T. nudiflora plywood and market plywood respectively. The evaluated physical and mechanical properties of T. nudiflora plywood were also compared with some relevant results and standards reported earlier. Key Words: Plywood, Trewia nudiflora, Physical properties, Mechanical properties. doi: 10.3329/bjsir.v43i4.2249 Bangladesh J. Sci. Ind. Res. 43(4),581-587, 2008


2018 ◽  
Vol 11 (2) ◽  
pp. 134-140 ◽  
Author(s):  
Mohammad Jafar Royen ◽  
Abdul Wasim Noori ◽  
Juma Haydary

Abstract In this work, drying of tomato slices was studied in a laboratory scale batch dryer working at conditions specific for geographical locations with low ambient pressure and low relative humidity of air. Tomato is a perishable farm product with high moisture content. Despite their high value, tomatoes are subjected to wastage and spoilage during their seasonal period; to last longer after harvested, they need to be treated by drying. Drying is one of the most widely used methods of tomato preserving for a longer period of time. This study involves experimental work on tomatoes drying in a tray laboratory batch dryer with the dimensions of (490 × 330 × 310) mm, a load cell-force sensor (range: 0–5 kg), fan (speed: 0–2500 rpm), air flow sensor (0–150 l/min) and a temperature and humidity monitoring system. This study was aimed at the development of a suitable drying method for the production of dehydrated agricultural products under specific air properties and climate conditions such as low ambient pressure and low relative humidity. During the experiment, the average ambient pressure was 82 kPa, and the average relative humidity of air was 20 %. Drying characteristics of tomato slices were determined at three temperature levels, namely: 50 °C, 60 °C and 70 °C,and three air flow rates: 30 l/s, 40 l/s and 50 l/s, for each temperature level. In this study, the effect of temperature, air flow rate, and ambient conditions on the drying rate of tomato slices were studied. The results indicate that during the experiments, tomatoes were dried to the final moisture content of 32.2 % from 92 %. Drying time at 50 °C, 60 °C and 70°C, and air flow of 30 l/s was 17.80 h, 15.80 h, and 14.08 h, respectively. For the air flow rate of 40 l/s, the drying time was 15.0 h, 12.9 h and 11.7 h and for the air flow rate of 50 l/s, the drying time of tomato slices was 14.0 h, 11.6 h and 10.2 h, respectively.


Sign in / Sign up

Export Citation Format

Share Document