Abstract: Conservation works in Malaysia that is procured by
public organisation usually follow the traditional approach where the
works are tendered based on Bills of Quantities (BQ). One of the
purposes of tendering is to enable the selection of a competent
contractor that offers a competitive price. While competency of the
contractors are assessed by their technical knowledge, experience and
track records, the assessment of pricing will be dependent on the
tender amount. However, the issue currently faced by the
conservation works sector is the difficulty in assessing the
competitiveness and reasonableness of the tender amount due to the
high variance between the tenders amount. Thus, this paper discusses
the factors that cause difficulty to the tenderers in pricing
competitively in a bidding exercise for conservation tenders. Data on
tendering is collected from interviews with conservation works
contractors to gain in-depth understanding of the barriers faced in
pricing tenders of conservation works. Findings from the study lent
support to the contention that the variance of tender amount is very
high amongst tenderers. The factors identified in the survey are the
format of BQ, hidden works, experience and labour and material
costs.
Abstract: Poly(lactic acid) (PLA) is a biodegradable polymer
which has good mechanical properties, however, its brittleness limits
its usage especially in packaging materials. Therefore, in this work,
PLA based polyurethane films were prepared by synthesizing with
different types of isocyanates; methylene diisocyanate (MDI) and
hexamethylene diisocyanates (HDI). For this purpose, PLA based
polyurethane must have good strength and flexibility. Therefore,
polycaprolactone which has better flexibility were prepared with
PLA. An effective way to endow polylactic acid with toughness is
through chain-extension reaction of the polylactic acid pre-polymer
with polycaprolactone used as chain extender. Polyurethane prepared
from MDI showed brittle behaviour, while, polyurethane prepared
from HDI showed flexibility at same concentrations.