Tannin/furanic based abrasive discs

Responsable scientifique : Antonio Pizzi (UMR 1092 Laboratoire d’Etude des Ressources Forêts-Bois – LERFOB)

Partenaires Labex : CRITT Bois

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Context — A new 100% biosourced thermosetting plastic material, based on the coreaction of bark-derived condensed tannin/furanic thermosets has been prepared and characterized by the LERMAB. This new material is synthesized by tannin and furfuryl alcohol, both relatively inexpensive plant-derived chemicals. The high mechanical resistance of this material lets envisage the development of several industrial uses and products for such a resin. The first application to be investigated in this proposal is the development of abrasive discs and wheels in which the resin derived from natural resources substitutes the presently used oil-derived phenol-formaldehyde resins. This entails the mixing and optimization of abrasives with the resin, the improvement of the interfacial compatibility between resin and abrasive, and the mechanical testing of the optimized product obtained under a variety of operative conditions.

An initial investigation on the possibility of preparing automotive and industrial brake pads in which the present phenolic resins are substituted by the resin 100% derived from renewable materials is also envisaged by addition of thermar resistant fibers such as carbon or boron fibers. This second part, if encouraging results are obtained, will be further pursued at a later stage with an automotive brake pads manufacturer.

The project places itself in the theme of increasing the competitiveness of the wood sector by developing new tailored innovative green products derived from wood biomass. In this context, the project aims at developing  hard plastics for a number of industrial applications to substitute oil-derived resins in both an economically viable quest as well as for the utilization of resources, such as bark, which are currently widely underutilized and undervalued. The target of this project are high value-added products for extensive use.

Objectives —We propose to develop and test a new abrasive wheels material for angle grinding applications in the metal and building industry the matrix being a natural biosourced resin issued from agriculture. The work will be eventually extended to brake pad linings for the automotive market.

Preparation of high value-added products for extensive use based on a new 100% biosourced thermosetting plastic material, based on the co-reaction of bark-derived condensed tannin/furanic thermosets already developed and characterized by the LERMAB research unit. This new material is synthesized by tannin and furfuryl alcohol, both inexpensive plant-derived chemicals.

Approach —We will focus on the grinding wheels material first, with progressively increasing the proportion of the grinding material over the natural matrix resin and finally to optimize the proportion of the two as regards abrasiveness, flexural strength and mechanical resistance at high revolutions per minute.

Highly resistant (a) abrasive diks, (b) cutting and moulding disks for angle grinderrs and (c) automotive brake pads have been prepared

Key results —

• The cytting and molding disks for angle grinders sand easily cut through stainless steel and their effectiveness is nearly comparable to commercial disks bonded with oill-derived synthetic resins.

• The abrasive disks prepared perform better and for a longer duration than abrasive disks prepared with synthetic matrix resins
• The automotive brake pads perform better than commercial brake pads bonded with synthetic resins allowing for the same level of use while allowing for a shorter stopping distance than what commercial brake pads provide.

Main findings — The hard plastic used for all the above applications revealed itself to be very strong and at worst comparable to synthetic resins and often superior to the performance of synthetic resins.

Future perspectives — The products prepared are only an initial example of what can be achieved with this hard biosourced thermoset material. Further development has been planned for the three developed products and additional product applications will be researched.