NIP REPORT January 2006- May 2007 - The UP College of Science ...

quantitative measurement of plasma cleaning efficacy. The cleaning process will also be
assessed if it is applicable to epoxy materials on top of polyimide layer.
a. CHED Visiting Professor Grant
Project Title: Development of gas discharge ion source for polymer treatment
Duration: August 2006 to July 2007
Amount/Fund: PhP 100,000.00
Goals
Produce high-grade wood with high water repellency, anti-termite and flameretardant
characteristics. The technique is an alternative method of wood
preservation offering a sterile procedural environment which renders the use of
chemicals totally irrelevant,
Surface modify other organic/inorganic polymers such as textile, abaca and
polytetrafluoroethylene materials to produce advanced materials with high
hydrophobic or hydrophilic properties depending on intended use,
Develop instrumentations to quantify the changes in surface characteristics
brought about by the irradiation process.
The GDIS was used as test facility to produce and study the characteristics of diffused,
low-energy hydrogen beams. Calculations using the optical relations of the device’s electric pole
pieces show that the GDIS has a negative focal strength. That is, the beams generated by the
device have shower-like configurations hence the acronym LEHIS for Low Energy Hydrogen
Ion Showers. This particular beam shape is most suitable for surface processing of polymers as it
modifies polymeric surfaces without destroying their bulk properties.
Wood was used as the initial target material for this research. The study, using
experimental and statistical techniques have shown that LEHIS treatment of wood enhanced its
anti-moisture and anti-fire attributes. LEHIS was found to be equally as effective as Permethrin
(a strong pyrethroid toxin) in minimizing attacks from subterranean termites. Spectroscopy using
a cast steel mass analyzer indicated a predominance of H + with faint signals of H2 + in the ion
showers. The monatomic ion plays an essential participatory role in the attribute enhancement
process. It is shown that wood affinity to water decreased as the proportion of H + increased, i.e.
higher flux density ratios favored surface inactivation. It is further demonstrated using hardwood
samples that a dominance of H + also improved fire resistance. H + ions seemed to be the initiator
in the formation of hydrophobic and flame resistant wood surfaces at the same time rendering
wood unpalatable to certain termite species (in particular, subterranean termites). Scanning
electron micrographs showed subsequent smoothening of topographic features for the irradiated
substrates. The images of treated samples showed diminished voids and partial closures of
surface micro-pores. The method proved benign showing no unfavorable effects on paint
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