Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Combating Bacteria Via Silver-Dammar Coating

27.02.2015

Natural resins obtained from plants to be used as a coating element to enhance durability and anti-rust properties.

Coating systems are formulated using a mixture of dammar, silver and nanoclay in varied compositions. Generally the problems in the coating area are poor coat quality, poor adhesion, long curing time period, corrosion attack, attachment or bacteria attack which could also cause corrosion attack which is called as Microbiologically Influenced corrosion (MIC). These disadvantages of coating system and coating surface could lead to coating failure thus leading to substrate damage especially metal substrate.

Materials: Dammar or triterpenoids resin are natural resins which can be isolated or obtained from plants that belong to the family Dipterocaupecea sp. Dammar is well known for its glossy properties and the plant can be found abundantly in Sarawak, Malaysia. Thus, it can be used in the coating industry. The role of the dammar is to improve the adhesion property, self cleansing property and shorten the coating curing time. Silver nitrate has quite a long history of usage as an antibacterial agent.

Silver possesses good antibacterial activity. The addition of silver onto the coating system, introduces the antimicrobial property for the coating system. It is used in a variety of applications for example as protective coating for concrete, brick, wood, metal and others. It is considered as a good anti-microbial coating due to its low toxicity to where the toxicity is lower than of bacteria. However, the antibacterial activity depends on the Ag+ ions released by the silver.

If it is too high, it will result in cytotoxicity. Thus to overcome this problem nanoclay was added into the coating system. Clay is a good absorbent which belongs to the phyllosilicate group. In this case Montmorillonite clay was used as the absorbent. Montmorillonite clay form could absorb compound and store it in the pore without leaching out the compound to the surrounding environment.

Methodology: In this research work, the polyol is modified by using a solvent and mixed with dammar in varied compositions. Silver nitrate is incorporated into the optimum composition of polyol-dammar, followed by a small amount of Nano clay is dispersed into the modified Silver-polyol-dammar mixture. Then the paint mixture is spin coated onto polished Aluminium Q-panel as a substrate and is left to dry at room temperature.

This research describes the characteristics of the dammar based paint system. Adhesion property is evaluated by using crosshatch test and pull-off test. The crosshatch test method is based on ASTM D3359 standards. The wettability property of a coating is characterized by using contact angle measurement. The resistances of paint systems are also described against microbial activity by using disc diffusion and agar well diffusion method.

The results: The result of crosshatch and pull-off test shows that the coating system containing 50 wt. % of dammar (50 PD) exhibits an excellent adhesion property. The addition of dammar to polyol helps to increase the contact angle measurement up to approximately 50 degrees. The antimicrobial activity of silver nanoclay coating was demonstrated by using disc diffusion and agar well diffusion method.

The antimicrobial activity was evaluated against a few negative gram bacteria and positive gram bacteria. K. pneumoniae, E. coli, S. aureus, P. aeruginosa and B. subtilis. Moreover it is also tested against fungi, C. albicans (fungi). The largest inhibition diameter zone against E. coli and S. aureus is obtained for the silver nanoclay polyol dammar, namely PDS3 coating system.

Azizah Hanom Binti Ahmad

Institute of Science (IOS),
UiTM Shah Alam, Selangor Darul Ehsan,
Malaysia
Email: azizahanom@salam.uitm.edu.my

Darmarajah Nadarajah | ResearchSEA
Further information:
http://www.uitm.edu.my
http://www.researchsea.com

Further reports about: E coli adhesion antibacterial antimicrobial coating coating system fungi

More articles from Process Engineering:

nachricht Etching Microstructures with Lasers
25.10.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Applying electron beams to 3-D objects
23.09.2016 | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>