New environmentally-friendly mortar reduces heat loss

Revolutionary Insulating Mortar: Newcastle University’s Breakthrough with Recycled Plastic and Aerogel

Newcastle University researchers have developed a groundbreaking new mortar that dramatically improves insulation while tackling plastic waste. This innovative material combines recycled plastic with silica aerogel, offering a sustainable solution for the construction industry.

Slashing Heat Loss and Reducing Plastic Waste

The team’s primary goal is to create a building material that minimizes heating and cooling costs and addresses environmental concerns. By replacing traditional sand with silica aerogel and recycled PET plastic, they’ve achieved just that.

Aerogels are renowned for their exceptional insulating properties. They are increasingly utilized in various sectors, including building construction and aerospace, to enhance thermal performance.

Remarkable Performance: Up to 55% Reduced Heat Loss

Published in the journal Construction and Building Material, the research demonstrates that this new mortar mix reduces heat loss by up to an impressive 55% compared to conventional mortar. Crucially, it still maintains the structural integrity required for masonry construction.

The mortar also meets stringent international standards (BS-EN 413-1:2011, ASTM C270-10, AS 1012/AS 3700). This makes it a viable, eco-friendly alternative for building energy-efficient and sustainable structures.

This innovative mortar is particularly effective in mitigating thermal bridging, frequently occurring in gaps between bricks where traditional mortar is used.

Professor Lidija Šiller, Professor of Nanoscale Science at Newcastle University’s School of Engineering and a lead author of the study, stated, “This study demonstrates that our formulation utilizing recycled PET plastic waste can produce cement-based mortars, offering an effective way to lessen their environmental impact. Wouldn’t it be wonderful to lower heating bills for all our new builds while simultaneously making a significant dent in global plastic waste?”

The Innovative Mortar Mix: Composition and Testing

The research team rigorously tested seven different formulations alongside a traditional mortar control group. The optimal mix consisted of 7% untreated silica aerogel (replacing natural sand) and 3% recycled PET (polyethylene terephthalate) plastic.

The PET plastic particles were sourced from shredded plastic bottle waste. These particles were coarse, irregular in shape, and measured between 2.5-3.5 mm. The scientists thoroughly washed the plastic pieces with water after shredding and allowed them to air dry for 24 hours.

The team meticulously analyzed key properties, including setting time, flowability (a measure of workability), density, strength, and thermal conductivity.

The Most effective Formulation:

• 7% untreated silica aerogels (replacing natural sand).
• 3% recycled PET (polyethylene terephthalate) plastic.

The novel formulation achieved a remarkable reduction in thermal conductivity of up to 55% compared to standard mortar samples.

Kaniaw Marof, PhD researcher at the School of Engineering and lead author of the study, added, “Improving the thermal performance of masonry buildings is a key focus in modern construction. It reduces the energy needed for heating and cooling, ensuring user comfort. In our work, modifying the surface of the silica aerogel particles was critical for successfully integrating them into the cement binder and PET plastic.”

Future Applications: Real-World Testing and Beyond

The scientists are actively pursuing the next phase: testing the new mortar mix in large-scale, real-world construction projects.

Professor Šiller explains, “Our new reduced thermal heat mortar, incorporating plastic and aerogels, meets all British standards. Our next step is to collaborate with partners, such as a construction company, to secure funding and construct a house using our mortar ‘recipe.’ This will provide direct evidence of potential energy savings and allow us to assess the economic viability for masonry building applications.”