Insulating Mortar with Unicellular Microspheres
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current thermally insulating mortars for building surfaces have limited thermal conductivity and often compromise on mechanical properties and cohesion, with existing additives like cork particles, expanded polystyrene beads, and perlite not achieving thermal conductivity values below 111 mW/m.K without significant cost or performance issues.
Innovation Solution
A powder mortar comprising at least 75% thermally insulating additives in the form of unicellular microspheres with a closed external shell and low thermal conductivity, specifically designed to maintain cohesion and mechanical performance, using a combination of inorganic and organic microspheres with a real density less than 0.25, and a hydraulic binder to ensure watertightness and cost-effectiveness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional thermally insulating additives (cork particles, expanded polystyrene beads, perlite) are used in mortars, then thermal insulation is provided, but thermal conductivity remains limited to 90-111 mW/m.K and mechanical properties deteriorate
Solution Approach 1:
The patent changes the size parameter of insulating additives from millimeter scale to micronic scale (maximum average external characteristic dimension less than 0.5 mm, preferably less than or equal to 0.2 mm). This parameter change enables achieving thermal conductivity below 55 mW/m.K while maintaining mechanical properties, as the fine microspheres create a more uniform distribution and better interfacial bonding in the mortar matrix.
Solution Approach 2:
The patent uses composite microspheres comprising a shell material (such as glass, ceramic, or polymer) and a core material (such as expanded polystyrene, air, or other low-density materials). This composite structure provides both excellent thermal insulation (thermal conductivity less than or equal to 55 mW/m.K) and mechanical strength, resolving the contradiction between insulation performance and mechanical properties.
2Temperature
If insulating additives are used to reduce thermal conductivity, then thermal insulation improves, but cohesion of the mortar layer deteriorates
Solution Approach 1:
The patent changes the size parameter of additives to micronic scale (less than 0.5 mm, preferably less than or equal to 0.2 mm), which improves cohesion by enabling better distribution and stronger interfacial bonding with the mortar matrix, while maintaining excellent thermal insulation performance.
Solution Approach 2:
The patent uses microspheres with a shell structure that provides localized mechanical strength at the particle-matrix interface, while the core provides thermal insulation. This local quality differentiation allows the mortar to maintain both cohesion and thermal insulation performance.
3Temperature
If lower thermal conductivity values are achieved using existing additives, then thermal insulation improves, but cost increases significantly
Solution Approach 1:
The patent uses composite microspheres that combine inexpensive core materials (such as expanded polystyrene or air) with thin shell materials (glass, ceramic, or polymer). This composite approach achieves superior thermal insulation (thermal conductivity less than or equal to 55 mW/m.K) at a lower cost compared to using expensive conventional additives like cork or perlite in high concentrations.
Solution Approach 2:
The patent changes the size parameter to micronic scale, which allows achieving lower thermal conductivity values with a lower volume fraction of additives, thereby reducing material cost while maintaining or improving insulation performance.
4Temperature
If millimetric insulating additives are used, then thermal insulation is provided, but water retention increases degrading insulating properties
Solution Approach 1:
The patent changes the size parameter from millimeter to micronic scale (less than 0.5 mm, preferably less than or equal to 0.2 mm), which reduces water retention by minimizing the surface area available for water absorption while maintaining thermal insulation performance through the fine particle distribution and shell structure.
Solution Approach 2:
The patent uses microspheres with a shell structure that acts as a barrier to water penetration. The shell (made of glass, ceramic, or polymer) prevents water from reaching the core material, thereby maintaining insulating properties even in the presence of moisture.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution achieves a drastic reduction in thermal conductivity to below 55 mW/m.K while maintaining satisfactory cohesion and mechanical performance, ensuring durability and cost-effectiveness for both new and renovation projects, with the microspheres remaining watertight and free of additional hydrophobic coatings.
Implementation Method 1
thermal conductivity less than or equal to 55 mW/m.K, the additives being waterproof
Implementation Method 2
the additives being waterproof, and at least 20% by volume of powder of said additives, called insulating microspheres, being unicellular, that is to say having a closed external shell delimiting a heart formed of a single internal cavity
Data Source
Figure 1
Figure 3~4
Figure 5
AI summary
The present invention relates to a powder mortar optionally mixed with water, including a mineral hydraulic binder, at least 75% in mortar powder volume of thermally insulating additives substantially in the form of beads and having a thermal conductivity lower than or equal to 55 mW/m.K. The thermally insulating additives are water-tight, and at least 20% in mortar powder volume of said additives, referred to as insulating microspheres, are of the single-cell type, i.e. with a closed outer shell defining a core comprising a single inner cavity, and are micronic with a maximum average outer characteristic size lower than 0.5 mm. The invention also relates to such a mortar as a layer or in the form of a plate or brick or in any other appropriate form.