Patrick H. Mabilog (March 2007)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Jackfruit is a lumber popularly used by the Filipinos in the construction of top plates, but it is also the least resistant to temperature change. When Jackfruit lumber is exposed to high temperatures, it shrinks.
This study aimed to determine the percent change in dimensions- namely length, width and thickness- and the percent change in weight attributed to moisture loss of Jackfruit lumber when exposed to various temperatures.
Nine Jackfruit lumber samples were exposed to test temperatures of 60°, 70°, and 80° Celsius for 6 hours with the use of an oven. Three samples were heated in each temperature. Length, width thickness and weight were measured before and after the expanse of heating with a vernier caliper. The percent change in dimensions and percent change in create were then determined.
Results of the study showed that test temperature for 80°C showed that greatest mean percent changes in dimensions and weight were found in test temperature of 80°C.
One-way Analysis of Variance showed that there was no significant difference on the percent change of length, thickness , and weight of Jackfruit wood when exposed to 60°, 70°, and 80° Celsius for 6 hours, but that there was significant difference noticed in the change width when exposed to three various temperatures (p=0.037, a=0.05). Test temperatures 70° and 80° Celsius showed the highest percent change in width and 60°C showed to lowest.
It is therefore concluded that exposure to different temperatures affects the width of jackfruit lumber but not change in length , thickness and moisture loss.