Scientists Create “Puff Pastry Concrete” That Resists Cracking, Is 20 Times Tougher and Provides Superior Thermal Insulation Than Ordinary Concrete

Concrete is one of the most widely used construction materials in the world. From houses and bridges to roads and skyscrapers, modern infrastructure depends heavily on it. However, conventional concrete has a major weakness: despite its impressive strength, it is relatively brittle. When exposed to earthquakes, sudden impacts or extreme loads, cracks can spread rapidly, sometimes leading to dangerous structural failures.

Now, scientists have developed an unusual new type of cement-based material inspired by something commonly found in bakeries: puff pastry.

The newly developed material, called Puff Pastry Architected Cementitious Material (PPAC), uses a specially designed layered structure to make cement-based materials significantly tougher while also improving their ability to prevent heat transfer.

Developed by a research team led by Kailun Xia, this innovative material combines two highly desirable properties: exceptional resistance to fracture and effective thermal insulation. Even more interestingly, it can be manufactured using a relatively simple rolling-and-folding process under normal room conditions.

The findings could open new possibilities for safer, more energy-efficient and more resilient buildings.

Why Conventional Concrete Has a Major Weakness

Concrete is widely used because it is affordable, durable, easily available and capable of supporting enormous loads. However, it has an important mechanical limitation: low fracture toughness.

Fracture toughness describes how effectively a material resists the growth of existing cracks. A material with low fracture toughness can break suddenly once a crack begins spreading.

This becomes particularly dangerous during earthquakes, explosions, accidental impacts and other extreme events. Instead of gradually deforming and absorbing energy, conventional concrete can experience sudden brittle failure.

Scientists have attempted to solve this problem by adding steel reinforcement, fibers and polymers to concrete. These approaches improve its mechanical performance, but the improvements in toughness and ductility are often relatively limited.

Another challenge is thermal insulation.

Ordinary concrete allows heat to pass through relatively easily. Consequently, buildings constructed with conventional concrete may require significant energy for air conditioning and temperature regulation, particularly in regions with hot climates.

Lightweight foamed concrete can provide better insulation, but improving its thermal performance often comes at the expense of mechanical strength.

Scientists therefore need a material that can provide both excellent structural performance and effective thermal insulation without making manufacturing complicated or expensive.

Inspired by the Structure of Puff Pastry

To address these challenges, Kailun Xia and his research team developed a new cementitious material inspired by the layered structure of puff pastry.

Anyone familiar with puff pastry knows that it contains multiple thin layers separated by small gaps. These layers give the pastry its characteristic flaky structure.

The researchers borrowed this structural concept and applied it to cement-based materials.

Their newly developed PPAC consists of alternating layers of solid cementitious material and thin, plate-like cavities. These layers are arranged in a highly organized pattern, creating a lamellar architecture at the microscopic scale.

Unlike ordinary concrete, where the material is relatively uniform, this engineered structure contains carefully arranged interfaces and cavities.

The design is important because it changes how cracks move through the material and how heat travels across it.

Instead of allowing cracks to spread directly through the material, the layered architecture forces them to follow more complicated paths. This helps distribute mechanical energy and prevents sudden fracture.

At the same time, the cavities act as barriers to heat transfer, improving thermal insulation.

A Simple Manufacturing Process Makes It Different

One of the most important features of this discovery is not just the material's performance but also how it is manufactured.

Many previously developed architected cementitious materials require complicated manufacturing techniques, including 3D printing, ice templating, hot pressing, laser cutting and special molding processes.

Some methods also require freezing, heating, vacuum treatment or repeated freeze-thaw cycles.

These procedures consume considerable time and energy, making large-scale production difficult.

The new PPAC material takes a different approach.

Inspired by puff pastry preparation, the researchers developed a simple rolling-and-folding technique.

The process uses hydrogel to help create the layered structure and weak interfaces inside the cementitious material. The material is repeatedly rolled and folded to produce alternating solid layers and thin cavities.

Importantly, the entire fabrication process can be performed under ambient conditions.

It does not require hot pressing, freezing or complicated molding procedures.

This approach could make production faster, more flexible and potentially more affordable. It also allows researchers to create components with different shapes and larger dimensions.

The team demonstrated that the material could be adapted to different geometries, an important requirement for practical construction applications.

Nearly 20 Times Higher Fracture Toughness

The mechanical performance of PPAC is particularly impressive.

According to the research findings, the material achieves a specific fracture toughness of approximately 91 MPa·mm⁰·⁵/g·cm³.

This is around 20 times higher than that of conventional cast cementitious material.

The improvement is significant because it means the new material can resist crack growth much more effectively.

Its layered architecture produces several mechanisms that help prevent fracture.

First, when a crack encounters the alternating cement layers and cavities, it cannot always continue along a straight path. Instead, it is forced to change direction, a process known as crack deflection.

Second, the layered structure creates mechanical interlocking between different regions. This helps resist separation and allows the material to absorb more energy before complete failure.

Third, the layers can slide and interact with one another, helping dissipate energy during deformation.

Together, these mechanisms produce a more ductile fracture response compared with conventional cementitious materials.

Interestingly, the material maintains a specific flexural strength comparable to that of ordinary cast cementitious materials.

This means its improved resistance to fracture does not come simply from sacrificing its bending strength.

The researchers also report that its fracture toughness exceeds that of conventional fiber-reinforced and steel-reinforced cementitious composites, approaching the performance of certain polymers and advanced technical ceramics.

Better Thermal Insulation With 68.3% Lower Conductivity

The second major advantage of PPAC is its ability to reduce heat transfer.

The material has a thermal conductivity of approximately 0.38 W/m·K.

This represents a 68.3% reduction compared with conventional cast cementitious material.

Thermal conductivity measures how easily heat travels through a material. Lower values generally indicate better thermal insulation.

The improvement comes largely from the material's organized cavities.

These thin cavities interrupt the pathways through which heat normally travels. As a result, heat transfer becomes less efficient.

This is particularly useful for buildings because better insulation can help maintain comfortable indoor temperatures.

In hot climates, it could reduce the amount of heat entering buildings, potentially lowering the need for air conditioning. In colder environments, improved insulation could help reduce heat loss.

Another important finding is that PPAC provides better thermal insulation than lightweight cementitious materials with comparable densities.

This suggests that carefully designing a material's internal architecture can be more effective than simply reducing its density.

What Could This Mean for Future Buildings?

The combination of high fracture toughness and thermal insulation makes PPAC an interesting candidate for next-generation infrastructure.

Its improved resistance to crack growth could help reduce the risk of sudden structural failure during earthquakes, impacts and other extreme events.

Its thermal insulation properties could also contribute to more energy-efficient buildings.

Potential applications include:

• Earthquake-resistant structures: Improved crack resistance could help enhance structural resilience.

• Energy-efficient buildings: Better insulation could reduce heating and cooling requirements.

• Protective infrastructure: Its ability to absorb fracture energy could be useful in structures exposed to sudden impacts.

• Lightweight construction components: Its layered architecture could support the development of multifunctional building materials.

• Customized architectural components: Its flexible manufacturing approach could allow the production of different shapes and geometries.

However, these are potential applications rather than proven real-world uses. More testing is necessary before the material can be adopted in large construction projects.

What Challenges Remain?

Despite its promising performance, PPAC is still at an early stage of development.

The researchers acknowledge that several challenges must be addressed before it can be used widely in construction.

For example, its compressive strength needs further optimization because buildings and infrastructure must withstand substantial loads.

Scientists also need to investigate how the material performs when manufactured in different sizes and thicknesses.

Long-term durability is another important question. Real infrastructure must withstand moisture, temperature changes, weather exposure, repeated loading and other environmental conditions for decades.

The research team also plans to explore whether the same design can be applied to mortar, conventional concrete and fiber-reinforced composites.

Industrial manufacturing will require further development as well. Although the current rolling-and-folding process is relatively simple, automated production systems will be needed to ensure consistent quality and efficient large-scale manufacturing.

Robotics, additive manufacturing and industrial automation could potentially help transform the laboratory technique into a practical production process.

A New Direction for Construction Materials

The development of puff pastry-inspired cementitious material demonstrates how controlling the internal structure of a material can dramatically change its performance.

Instead of relying only on stronger ingredients or additional reinforcement, researchers have shown that arranging cement into carefully designed layers can improve its resistance to cracking while reducing heat transfer.

With approximately 20 times higher specific fracture toughness and 68.3% lower thermal conductivity, PPAC represents a promising step toward multifunctional construction materials.

Although further research is needed before it reaches real-world buildings, the concept could help scientists develop future infrastructure that is not only stronger and safer but also more energy-efficient.

Perhaps the future of concrete will not depend only on what it is made of, but also on how its internal layers are designed.

Reference: Xia, K., Chen, Y., Liu, X. et al. Tough, thermal insulating and scalable puff pastry-inspired architected cementitious material via simple rolling-folding. Nat Commun 17, 10244 (2026). https://doi.org/10.1038/s41467-026-77120-z