Research topics:

• Development of Fiber Reinforced Geopolymers composites (FRGP) as Structural Strengthening Material for Brick Masonry
• Use of fly ash for requalification of industrial wastes
• Geopolymer panels systems
• Use of geopolymer activators as catalyst for fired clay bricks with low energy consumption.
• Geopolymer furniture elements
• Archaeometric Investigation on Geopolymeric Binders of Roman Water Works (Opus Signinum) in Verona.
• Geopolymers in the restoration of pottery, ceramics and bricks

Figure 1 shows some examples of prototype obtained in ICMATE labs: In clockwise order from top left: prototype of decorative furniture item, geopolymer mortars as adhesives to bond fiber reinforcements onto brick masonry - test samples for shear and pull-off mechanical tests, Prototype of a sandwich panel with a geopolymeric structural layer, prototypes of functional furniture elements obtained by mold casting of geopolymers.

Depending on the their composition and the preparation method geopolymers can present several technologically interesting properties:

• excellent resistance to high temperatures, up to 1200oC
• excellent chemical resistance both towards organic solvents and acid or basic aqueous solutions
• good mechanical properties with compression strength up to 100 MPa
• ability to form porous materials via foaming during geopolymerization or low porosity by choosing suitable formulations and adequate processing conditions
• short setting times
• low shrinkage and ability to reproduce fine mold details
• good compatibility with steel reinforcements in concrete structures due to their high pH and low Cloride ion penetrability
• excellent long term stability useful in the inertization of waste materials
• user friendly process: no use of toxic substances, minerals used are biologically inert and the acqueous solutions used are moderately alkaline.

Besides the above mentioned properties, probably the main reasons behind the recent increased interest in geopolymers lies in their green chemistry :

• geopolymers are high performance cementitious materials that could substitute Portland cement, avoiding the high-temperature treatment of limestone required in Portland cement clinker production, thereby potentially reducing the global CO2 emission of the cement industry from 5% to 1%.
• geopolymers can be made by using a vast number of different waste materials, including among others furnace-slag, coal fly ash, rice-husk ash, micronized waste glass, etc… the only requirement being that they have pozzolanic activity.

The Geopolymer research group at ICMATE institute in Padova is active since 2010.
The activity of the group is directed towards applied science, carried out in collaboration with academic partners (University of Padova), with local and national small and medium enterprises and with Sovrintendenza ai Beni Culturali del Veneto.
The study on geopolymers is carried out principally starting from a chemical perspective using the longstanding experience of the group members in the characterization of organic and inorganic materials. The research is carried out using the availability of a wide range of experimental techniques at ICMATE:

• X-ray powder diffractometry
• NMR spectrometry (AVANCE3 300 with Multinuclear Solid State MAS Probe)
• Electron microscopy and micro-analysis (FEG-ESEM-EDS-EBSD)
• TGA-DTA
• ICP -optical emission spectrometer
• Micro-FTIR
• optical microscopy

The chemical characterization is complemented by processing and mechanical techniques using the following equipment:

• programmable high temperature Furnace (1400°C)
• Mechanical press for compression (50KN) and 3-point bending tests (5KN)
• Climatic chamber allowing freeze/thaw cycles, UV irradiation, etc..

Research topics:

• Development of Fiber Reinforced Geopolymers (FRGP) as Structural Strengthening Material for Brick Masonry: investigation of geopolymers in substitution of mortars or organic resins as a matrix to bond fiber based structural reinforcements (basalt,steel, carbon, ..) to historic brick masonry to improve fire resistance, vapor transpiration and adhesion to substrates and fibers.
• Use of fly ash for requalification of industrial wastes
  Exploitation of the geopolymeric reactivity of fly-ash to produce bricks, waste inertization and concrete with low environmental impact.
• Panel systems and coatings for tecnological items. By using the good adhesion of geopolymers to a wide range of substrates (metals, glass, stone, concrete, some types of polymers,..) and the great variety of possible mix designs, different physical properties can be obtained (low weight, strength, color, thermal heat capacity and conductivity, …) allowing the fabrication or coating of technological items such as façade panels, heating/cooling panels, tiles.
• Use of geopolymer activators as catalyst for fired clay bricks with low energy consumption. Realization of clay bricks with good mechanical and bioclimatic properties at firing temperatures in the 400-500oC range instead of the usual temperatures > 1000oC.
• Furniture elements
  Development of geopolymer formulations for the realization of functional and decorative furniture items with suitable mechanical and aesthetical properties.
• Archaeometric Investigation on Geopolymeric Binders of Roman Water Works (Opus Signinum) in Verona. Characterization of Opus Signinum from roman water tanks and acqueducts in Verona via MAS NMR Spectroscopy and XRD to investigate their structural analogy to geopolymers.
• Geopolymers in the restoration of pottery, ceramics and bricks. The aim of the project is to test geopolymer adhesives for repair of historic ceramic and stoneware items.