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 Additive manufacturing, from macro to nano
11.04.2017 | Laser Zentrum Hannover e.V.

nachricht Dresdner scientists print tomorrow’s world
08.02.2017 | Fraunhofer-Institut für Werkstoff- und Strahltechnik IWS

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>