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The aim of this paper is to describe the preparation and characterisation of poly(methyl methacrylate) (PMMA) (Mw: 996,000) and dammar mixtures to obtain a new series of natural coating materials for application on mild steel substrates. Dammar is a natural resin extracted from Dipterocarpus Grandiflorus sp., or kruing trees, which grow mainly in the tropical Asia Pacific forest.

Natural dammar resin was mixed with PMMA at different weight percentages in xylene as a solvent and dammar as dominant component. The mixtures were applied on mild steel Q‐panels to form dry coating films. The coating films were investigated under Attenuated Total Reflection‐Fourier Transforms Infrared (ATR‐FTIR) technique to observe the presence of functional groups from PMMA and dammar. Resistivity of coating films against corrosive agents from electrolytes was measured by using potential time measurement (PTM) technique. ASTM D3359 (cross‐hatch) technique was used to measure the coating film adhesion strength on the substrate. The entire tests were conducted at 28°C.

Natural dammar resins is potentially applicable for coating on cold rolled mild steel Q‐panel when mixed with PMMA. Blended dammar resin with PMMA in 5:5 ratio (coded as DP50) was found to give the highest energy of rapid impact indenter. Cross‐hatch test under ASTM D3359 revealed that 50 percent w/w of dammar in PMMA had increased the adhesion strength of the coating film where there was no coating area peeling off from the substrate after the test. DP50 also had the longest time to resist penetration of electrolytes through the coating film when immersed in salt water.

Decreasing the amount of dammar lower than 50 percent weight ratio with PMMA will cause high viscosity and inhomogeneous mixtures.

Natural dammar resin mixed with PMMA (behaviour naturally in free standing film) for coating paint application was formulated.

The effect of using microcrystalline cellulose (MCC) as an additive in coating paint films for non-stick coatings was studied in this work. This paper aims to discuss the benefits of MCC blended in the coating paint film that consists of poly(methyl methacrylate) (PMMA) and dammar.

PMMA and dammar mixed at a specific Wt.% ratio with xylene as its solvent. Two sets of mixtures were prepared, where one mixture contained MCC and another, without. The mixtures were applied to metal substrates as coating paint films. The performance of the non-stick coating paint film was observed through the adhesive test between adhesion layers on the coating paint film and also through the cross-hatch test for the adhesion of the non-stick coating paint film to the metal substrate. The results correlate with the surface roughness and glossiness tests.

The results showed that for the coating paint films, Sample B consisted of 80:20 Wt.% ratio of PMMA-dammar with an addition of 5 Wt.% MCC had an excellent performance as non-stick coating paint films. The MCC formed microparticles on the surface of the coating paint film sample and this causes the coating paint film samples with MCC to develop a rougher surface compared to the coating paint film without MCC. Sample B coating paint film had the highest average surface roughness (Ra) of 383 µm. The cross-hatch test showed the coating paint film with the addition of MCC had stronger adhesiveness on the substrate’s surface thus prevents the coating from peeling off from the surface.

The developed coating paint film in this study would be suitable for outdoor applications to prevent illegal advertisements and stickers.

MCC added to the coating paint film improves the surface performance as a non-stick coating.

In this work, the blends of poly(methyl methacrylate), PMMA and poly(methyl vinyl ether-alt-maleic acid monoethyl ester), PMVEMA-ES are studied as organic coatings to evaluate the impact of intermolecular hydrogen bonding on the physical and thermal characteristics of the prepared coatings.

PMMA (Mw = 120,000 g mol-1) was chosen as our binder material. Due to the low adhesion property of PMMA on polar substrates, it was blended with PMVEMA-ES, which contains polar –COOH groups, to improve the adhesion and thermal properties of the coatings by forming intermolecular hydrogen bonds. A cross-hatch adhesion test was carried out to evaluate the adhesion strength of different ratios of PMMA/PMVEMA-ES blends as coatings. In addition, changes in the glass-transition temperature, Tg as the composition varies were studied using Differential Scanning Calorimetry, DSC. Then, glossiness and hiding power tests were also conducted to evaluate the physical properties of the prepared coatings.

Upon a closer look at the DSC results, it was found that blends consisting of 12.5, 25.0 and 87.5 wt. % PMMA were completely compatible due to the presence of only a single Tg in their thermograms. Other blend compositions showed two distinct Tgs, indicating partial compatibility. Furthermore, the addition of PMVEMA-ES caused the Tg of PMMA to shift to lower temperatures, a strong indication of intermolecular hydrogen bonding interactions between the two components. From the cross-hatch adhesion results, the addition of PMVEMA-ES improved the adhesion properties of PMMA coating, except for blends consisting of 62.5 and 75.0 wt. % PMMA possibly due to the partial incompatibility between the two components. These findings were further corroborated with the results of glossiness and hiding power measurements. The superior result was seen for the blend consisting of 12.5 wt. % PMMA with strong adhesion property, high glossiness, compatibility and high translucency.

PMVEMA-ES can potentially be used as an adhesion promoter in PMMA-based coating formulations.

This is the first report on the properties of PMMA/PMVEMA-ES blends as coatings.