Green thermosets Scientific Publications


green Thermosets – Nanocomposites of Rosin/Maghnite









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Green thermosets Project  Scientific Publications



1             Vidhura Mahendra, Dora Sousa and Geoffrey Mitchell “Rosin – an untapped green resource for the future for Portugal” – Vol 4 CDRSP knowledge series – Series Editors Geoffrey Mitchell and Paula Faria Institute Polytechnic of Leiria 2017 ISBN 978-989-96501-1-4 (print) and ISBN 978-972-8793-55-5 (e-book).

2             Geoffrey Mitchell, Florindo Gaspar, Vidhura Mahendra, Dora Santos “Advanced Materials from the Forests” in Handbook of Ecomaterials edited by Boris I Kharisov Oxana, Oxana Kharissova, Leticia M. Torres-Martínez Springer-Nature 2018 ISBN 9783319682549


Papers International Refereed Journals

1 G.R.Mitchell Climate Change and Manufacturing Procedia Manufacturing 12 298- 2017

doi: 10.1016/j.promfg.2017.08.033


In 1966, the World Meteorological Organization proposed the term climatic change to encompass all forms of varations in the climate variability on time-scales of greater than 10 years, whether the cause was natural or anthropogenic. When it was realized that human activities had a potential to drastically alter the climate, the term climate change replaced climatic change as the dominant term to reflect an anthropogenic cause. Climate change was incorporated in the title of the Intergovernmental Panel on Climate Change (IPCC) and the UN Framework Convention on Climate Change (UNFCCC). Since 1988, the IPCC has produced 5 multivolume reports which collate the consensus of all leading scientists across the globe on all aspects of the science of climate change.

At the Paris climate conference in December 2015, 195 countries agreed to the world’s first universal action plan to tackle climate change by limiting global warming to ‘well below 2 °C’. This historic achievement was just the beginning – now every country must turn their promises into action. We must give serious attention to adapting our processes to mitigate the effects of global warming. This paper reviews the current state of expectations and agreements and explores how manufacturing technology can contribute toward these programmes.


2 Vidhura Mahendra, Mahadevappa Y. Kariduraganavar, Nandini A. Pattanashetti,

Geoffrey R. Mitchell The Coconut Tree – a source of sustainable polymeric materials United Journal of Biochemistry and Biotechnology in press 2018 preprint available

Coconut is a versatile tree belonging to the palm family (Botanic term Arecaceae, coconut palms, Cocos nucifera) in which each part is used for numerous applications. It is grown in the tropic and subtropic regions of the world. There is a tradition and culture associated with the coconut tree due to its enormous value as a food commodity, the use of its branches and wood for daily needs. Coconut is typically cultivated in the coastal regions of the countries due to its preferred moistened soil and salty nature. As well as a source of food, coconut fibres are widely used due to its high strength material properties for many domestic applications. It is clear that the coconut tree can contribute materials without compromising on the supply of food in contrast to other sources of sustainable materials.



3 Sousa, D., Biscaia, S., Viana, T., Gaspar, M., Mahendra, V., Mohan, S.D., Mateus, A., Mitchell, G.R., 2019. Rosin Based Composites for Additive Manufacturing. Applied Mechanics and Materials 890, 70–76.


Rosins are the non-volatile exudates of pine resins with hydrophobic characteristics that are widely used as a precursor for many industrial applications. In this paper we discuss the nature, process and its applications as a matrix for a composite material for additive manufacturing. The composite material has been tailored to chemical and mechanical properties with respect to their applications.



  1. Mahendra, V., 2019. Rosin Product Review. Applied Mechanics and Materials 890, 77–91.

Rosin is the non-volatile exudate of pine resin with hydrophobic characteristics that are widely used and modified as a precursor for many industrial applications such as paints, inks and adhesives. The review paper discusses the rosin, its nature, processing, production material development for green science. The composite materials have been designed and tailored with respect to desired applications to offer a potential replacement of petrochemical use. Rosin consists of different resin acids that can undergo isomerisation at elevated temperatures and interchange its form, which, can be used as a rigid building block to manipulate their mechanical properties and crystallisation behaviours. Modified rosin epoxy binders have been recognised as materials with resistance to a wide variety of chemical conditions that can be used to fabricate a variety of reinforced constructions. Rosin has been employed in foam making in addition to composite material, depicting its ability as a crosslinker.



  1. Properties of Rosin Vinyl Imidazolium Based Compounds as Potential Advanced Biocompatible Materials. Waste Biomass Valor 11, 3723–3730 (2020).

Rosin is a natural material extracted from the pine tree that is vastly used as an adhesive in the construction industry. It chemically consists of cyclic carboxylic structure that is known as rosin acids or abietic acid and other isomers. The abietic acid or/and its isomers can structurally be altered to design for different applications. Herein we envisage the potentials of altering the rosin structure to investigate its thermal and physicochemical properties for advanced material applications. In this regard we have utilised the potassium rosinate (rosin soap) also known as the saponified rosin. Saponified rosin is reacted through an anion exchange metathesis process promoted by ultrasound, with either an ionic liquid or a poly(ionic liquid), namely the 3-octyl-1-vinylimidazolium bromide and the poly (3-octyl-1-vinylimidazolium bromide) as a scope to improve thermal and mechanical applications. The structures of these new compounds were determined using fourier transform infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance spectroscopy (NMR). The rosin/ionic liquid based compound found to be a better fitting candidate for advanced material applications, due to significant improvement in the thermal stability compared to the crude rosin (up to 70 °C raise in the thermal degradation) and promising mechanical characters such as elasticity and malleability.




6 Biopolymers Based on Rosin Mitchell GR, Mahendra V, Sousa D (2018). Curr Res Biopolymers: CRBP-102. DOI: 10.29011/CRBP-102. 000002

Rosin is a material, which can be obtained from pine resin using a green technology with no waste output. It is a mixture of terpenes with a functionality that make them a rich chemical resource. Rosin is a material which has been available for hundreds of years and has developed many niche applications some old, some new. The authors review the potential of this material for preparing sustainable biopolymers and composites by identifying the reaction paths. The authors conclude that foams and composites may be the most effective route to high volume applications based on rosin.



  1. Design, synthesis and cytology of pine derived resin composite scaffolds for tissue engineering

Submitted to Bipolymers expected publication in 2020


Vidhura Mahendra1, Geoffrey R. Mitchell1, Artur Mateus1, Pedro Morouço1, Nuno Alves1, Xuebin Yang2, Kenny Man2, Khoon Lim3, Catherine Chia3 and Tim Woodfield3


  1. Centre for Rapid and Sustainable Product Development, Polytechnic Institute of Leiria, Portugal1
  2. Faculty of Medicine and Health, School of dentistry, University of Leeds, UK2

  3. Christchurch regenerative medicine and Tissue Engineering group, University of Otago, New Zealand



Pine resins are widely used as an adhesive material for various construction applications and polycaprolactone (PCL) is a biodegradable polymer with potential applications for bone and cartilage repair. Even though PCL is a biomaterial, due to its hydrophobic nature has difficulties in cell adhesion in tissue engineering (TE). On the other hand, rosin is a sticky adhesive natural material extracted from pine resin that can be blended with PCL to alter its properties. In this work a series of porous rosin/PCL composite scaffolds were designed and fabricated via layer by layer bio-printing, a rapid prototyping technique. The composition of the material, microstructure and mechanical properties of the fabricated scaffolds were assessed and compared. The composite scaffolds were probed for their thermal degradation (TGA) with respect to PCL. The scaffolds were probed for cytotoxicity by cell seeding and evaluated for its biological properties. The research findings are a novel step in the advanced science and technology with related to natural product development and green chemistry with rosin as a potential biomaterial. 

Keywords: pine resin, polycaprolactone, composites, scaffolds, mechanical properties, cytology

8. Green Nanocomposites from Rosin-Limonene Copolymer and Algerian Clay

Hodhaifa Derdar 1, 2, Geoffrey Robert Mitchell 3,*, Vidhura Subash Mahendra 3, 5 4 , Mohamed Benachour 2, Sara Haoue 2, Zakaria Cherifi 1, 2, Khaldoun Bachari 1, Amine Harrane 2, 4 5 and Rachid Meghabar 6 2


1 Centre de Recherche Scientifique et Technique en Analyses Physico-Chimiques(CRAPC), BP 10 384, Siège ex-Pasna Zone Industrielle, Bou-Ismail CP 42004, Tipaza, Algeria; (H.D.); (Z.C.); (K.B.)


2 Laboratoire de Chimie des Polymères(LCP), Département de Chimie, FSEA, Oran1 University Ahmed Benbella BP N° 1524 El M’Naouar, 31000 Oran, Algeria; (M.B.); (S.H.); (R.M.)


3 Centre for Rapid and Sustainable Product Development, Institute Polytechnic of Leiria, Marinha Grande, Portugal; (G.R.M.)


4 Department of Chemistry, FSEI University of Abdelhamid Ibn Badis – Mostaganem, Algeria; (A.H.)


5 School of Chemistry Food Science and Pharmacy, University of Reading, Reading RG6 6AD,UK; (V.S.M.)* Correspondence:;Tel.: (+351) 244 569 441 | Fax: (+351) 244 569 444 Mobile (+351) 962 426 925 or (+44) 7768 978014. Received: date; Accepted: date; Published: date


Abstract: Green nanocomposites from Rosin-Limonene copolymers based on Algerian organophilic-clay named Maghnite-CTA+ (Mag-CTA+ 23 ) were prepared by in-situ polymerization using different amounts (1, 5 and 10 % by weight) of Mag-CTA+ 24 and Azobisisobutyronitrile as a catalyst. The Mag-CTA+ 25 is an organophilic montmorillonite silicate clay prepared through a direct exchange process, the clay was modified by ultrasonic-assisted method using Cetyltrimethylammonuim bromide in which it used as green nano-filler.The preparation method of nanocomposites was studied in order to determine and improve structural, morphological,
mechanical and thermal properties of rosin.The structure and morphology of the obtained nanocomposites (Ros-Lim/Mag-CTA+ 30 ) were determined using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electronic microscopy and transmission electronic microscopy. The analyses confirmed the chemical modification of clay layers and the intercalation of rosin-limonene copolymer within the organophilic-clay sheets. Exfoliated structure was obtained for the lower amount of clay (1% wt of Mag-CTA+ 34 ), while intercalated structures were detected for high amounts of clay (5 and 10% wt of Mag-CTA+ 35 ).The thermal properties of the nanocomposites were studied by thermogravimetric analysis (TGA) and show a significant improvement inthe thermal stability of the obtained nanocomposites compared to the pure rosin-limonene copolymer (a degradation temperature up to 280°C).

Keywords: Green nanocomposites; Rosin; Organoclay; Maghnite-CTA+

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