Development and characterization of modified silicone – dammar coating resin / Rosnah Zakaria

The purpose of this study is to develop and characterized the new modified silicone binder resin. The silicone, synthetic resin bought from Dow Corning Corp. and dammar bought from local supplier. Ten (10) samples were prepared and one of them was silicone resin without dammar. The samples were designated as SD0, SD5, SD10, SD15, SD20, SD25, SD30, SD35, SD40 and SD45. The mixture was coat onto aluminum q-panel using spin coater and left in room temperature for around 7 – 8 days for curing process. The cured samples were undergone the mechanical and electrochemical characteristic. The mechanical characterizations include viscosity, cross-hatch test, pull off test, wetting and impact test. Results for cross hatch test showed that 5-15 wt% of dammar in the silicone resin provide the better adhesion on aluminum q-panel with the edges of the cut are smooth and none of the square lattice detached. In the impact test, no fracture can be observed on the impact surfaces when the 1 kg load was released on SD0 – SD20 dried coating surfaces

Dammar Resin Degradation Revisited

Dammar, a natural triterpenoid resin, is widely used as a picture varnish in art technology. Several research workers have recently characterised its composition and oxidative degradation. Due to a lack of sensitivity, conventional thermal methods to characterise oxidation stability (like TGA and DSC) often require a high temperature regime. Chemiluminescence measurements turned out to be more sensitive (temperatures below 100 °C) and simultaneously allowed for better selectivity of the signal, which is directly coupled to the oxidation mechanism. The data collected here will enable an advanced kinetic modelling of Dammar degradation

The Rheological Characteristics of Dammar Mata Kuching

Rheology is already defined as the science of flow and deformation of matter. The purpose of rheology is to look at the relationships between stress and deformation of the material-marterial (non-Newtonian) in order to explain its mechanical properties. One of the ingredients that is often used as a basic material for making products is dammar. Dammar is a general term used to name a material in the form of natural resin which is the result of exudation of trees from the Dipterocarpaceae and Burseraccae families. This research uses raw materials dammar and toluene which are used to make a solution of dammar with the proportion of dammar: toluene, namely 50: 50, 40: 60, 35: 65, and 30: 70. Then the rheological analysis is analyzed by measuring the viscosity value, the shear rate. , and also its shear stress. The viscosity value increases with the greater the shear rate and the value of n (Flow Behavior index) is> 1, indicating that a solution of resin is a fluid with a type of dilatan fluid.   Keywords: dammar, deformation, rheology, shear rate, shear stress

The role of organic and inorganic indoor pollutants in museum environments in the degradation of dammar varnish

This paper investigates the effects of inorganic (NO2 and O3) and volatile organic acid (acetic acid) pollutants on the degradation of dammar varnish in museum environments. Model paint varnish samples based on dammar resin were investigated by Gas Chromatography Mass Spectrometry (GC-MS), Dynamic Mechanical Analysis (DMA) and Atomic Force Microscopy (AFM). Dammar is a natural triterpenoid resin, commonly used as a paint varnish. Samples were subjected to accelerated ageing by different levels of pollutants (NO2 and O3 and acetic acid) over a range of relative humidities (RH) and then analysed. The results revealed that as the dose of the pollutant was increased, so did the degree of oxidation and cross-linking of the resin. Most interestingly, it was shown for the first time that exposure to acetic acid vapour resulted in the production of an oxidised and cross-linked resin, comparable to the resin obtained under exposure to NO2 and O3. These conclusions were supported by the analyses of model varnishes exposed for about two years in selected museum environments, where the levels of pollutants had been previously measured. Exposures were performed both within and outside the selected microclimate frames for paintings. Results showed that varnishes placed within the microclimate frames were not always better preserved than those exposed outside the frames. For some sites, the results highlighted the protective effects of the frames from outdoor generated pollutants, such as NO2 and O3. For other sites, the results showed that the microclimate frames acted as traps for the volatile organic acids emitted by the wooden components of the mc-frames, which damaged the varnish

Biodeterioration patterns found in dammar resin used as art material

Since the middle of the XIX century, when dammar became popular in Occident, this natural resin is one of the most used in art painting techniques as final protective coating (varnish) as well as a component of pictorial media. The present work is the first approach to the study of the microbiological biodeterioration of this artistic material, which can seriously affect the appearance and integrity of works of art when bad conservation conditions -especially high humidity levels- take place. 12 microorganisms, fungi and bacteria, came from collection and from oil paintings affected by biodeterioration patterns, were inoculated on test specimens prepared with varnish dammar. These were incubated and analyzed by GC-MS to determine both the microbiological capacity of growth and chemical alteration on the resin. Some of the studied microorganisms have shown patterns of deterioration similar to those found in works dedicated to natural or accelerated photochemical ageing of triterpenoid varnishes.This study was supported by the National Spanish Project “I+D+I MCYT” CTQ2005-09339-C03-03

Change and continuity on the margins : livelihood transformation in Routa Southeast Sulawesi, Indonesia

My thesis studies the formation and transformation of livelihoods in the remote Routa sub-district. The findings arise from my experience living with people and engaging in their everyday lives. Through the perspective of households, I show how people diversify their livelihoods, to include forest gathering, swidden farming, staple food cultivation (particularly rice) and cultivating commercial food crops. I discuss the pathways of informal decisions that households use to negotiate inevitable change. The abundance of forest products attracts people from surrounding areas to migrate into Routa. The migrants, traders and local people all have their roles to play as agents of change on the frontier. Environmental change indicated by the dwindling availability of forest products, and the inevitable fluctuation of commodity market have driven the transformation of livelihoods in Routa. Migrants and traders disseminate information about livelihoods. Traders often become patrons who supply the provisions that enable households to adapt to the gradual transformation of their livelihoods. Low population density has led to the problem of seasonal labour shortages that to date have prevented people from obtaining sufficient income from any one particular livelihood. As a result, people have to utilise the labour of all household members and invited migrants to overcome labour shortages. To meet everyday needs and insufficient income, people diversify. A few still maintain their livelihoods as forest gatherers and swidden farmers. Change is also felt in the coming of the palm oil plantation in Lalomerui village. The palm oil company introduces a new working culture that few people can negotiate. A large multi-national mining company is also offering opportunities for local people. They established local criteria for employment, formed consultative groups and established a micro-finance institution in each village. But the success of pepper makes the presence of both big investments less meaningful in the lives and livelihoods of the local people

Application of ATR-far-infrared spectroscopy to the analysis of natural resins

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