Update of the progress

Major achievements M1-21 (Midterm report, dissemination summary)

The SIRENA Project is structured into Preparatory and Implementation Actions being supported by a set of actions devoted to Project Monitoring, Project Dissemination and Project Management. The implementation status of the project in the period covered from the 2nd January 2013 (official start date of the project) to the 30th September 2014 is hereby summarized.

A. Preparatory Actions

The preparatory actions for the period include the following actions:

A.1. Technological Surveillance and Benchmarking

The Technological Surveillance System (TSS) (Action A.1.) whose objective is to properly trace and asses relevant information in the areas of interest of SIRENA is being implemented with a total number of 185 inputs included in the database (30/09/2014). The outcomes of this system have been made freely accessible by means of registration in the project’s website.

A.2. Materials

Present action is divided into A2.1. Nanocomposites/NMs selection from each of the industrial sectors under evaluation; A2.2. Nanocomposites Manufacturing and A2.3. Verification of the improved performance.

The different combinations of nanofillers for each polymeric matrix in addition to the reference formulations have been defined. Carbon based nanoreinforcements (Carbon nanotubes –CNTs- and Carbon nanofibres –CNFs-) have been selected for the epoxy matrix (aeronautical applications); metal oxide nanoparticles (Silicon dioxide and Aluminium oxide) for the polyester (energy applications) and layered silicates (Wollastonite and Montmorillonite) for the polypropylene (automotive applications).

The selection and purchase of the specific types and grades of the matrices and nano-reinforcements has been performed and test materials have been manufactured using different techniques: calandering and curing in oven processes were used for the manufacturing of epoxy based nanocomposites; high speed mixer and casting processes were used for the manufacturing of the polyester based nanocomposites and, finally, extrusion and injection processes were used for the manufacturing of polypropylene based nanocomposites.

The next table described the final compositions of the test specimens:

 

MarketReference MaterialENMFormulations
AEROSPACE Epoxy (E) Carbon nanotubes (CNT)
Carbon nanofibres (CNFs)
Neat Epoxy
Epoxy + 2% CNTs
Epoxy + 2 CNFs
ENERGY Polyester SiO2 NPs
Al2 O3 NPs
Neat Polyester
Polyester + 2% SiO2
Polyester + 2% Al2 O3
ATUTOMOTIVE Neat Polypropylene
Polypropylene (PP) 20%
Talcum
Wollastonite (WO)
Montmorillonite (MMT)
Neat Polypropylene
PP + 20% Talcum
PP + 5% WO +2%MAPP
PP+ 5% MMT +2%MAPP

 

The improvement of the functionalities of the traditional formulations by the use of nanotechnology has been verified using standardized methods which are specific to the materials’ properties to be characterized (electrical conductivity and mechanical properties). As a consequence of the results of the verification, an additional batch of the polyester based nanocomposite has been manufactured with a reduced nanofiller loading (2% instead of 5%).

A.3. Methodologies

Present action is divided into A3.1. Evaluation of the different environmental exposure scenarios and A3.2. Evaluation of current technologies and protocols for environmental exposure assessment.

Different applications have been defined for the nanocomposite materials tested within SIRENA. In the case of aerospace applications the leading edge of the wing of an air plane manufactured of epoxy resin combined with carbonaceous nanomaterials for an increase of the electrical conductivity; for the energy sector a wind turbine blade manufactured of polyester combined with metallic NPs to increase mechanical performance and for the automotive sector, a drip cap manufactured from polypropylene combined with nanoclays in order to achieve the same mechanical properties with a reduced weight. The instructions provided by the ECHA (Environmental Chemicals Agency) for the estimation of the environmental exposure from articles have been followed in environmental exposure scenarios definition, having assimilated the nanomaterials used in nanocomposites manufacturing to fillers, as defined in the OECD Emission Scenario Document (ESD) on plastic additives. Several limitations to the proposed scenarios have been identified, mainly related to the nanocomposites production figures. The work conducted so far has been transferred to the OECD having obtained a positive response; the final version of the deliverable will integrate data related to the emission factors derived within SIRENA.

In the area of methodologies, 32 references related to the mechanical degradation of nanocomposites have been assessed in depth. The absence of standard operating protocols to be used for scenarios simulation makes inter-assays comparison highly challenging. Furthermore, two major critical steps have been observed in the nano-release studies conducted so far: the development of an appropriate set-up for nano-release assessment (confinement, clean air supply…) and the collection step in which released nano-objects are characterized.

A.4. Pilot experience

Present task is divided into A.4.1. Establishment of protocols for samples transference; A4.2. Preliminary protocol for exposure assessment drilling and crashing and A.4.3. Adequation of chambers and prototypes for dust generation.

A transnational access to VITO’s nanoaerosol exposure chamber in the frame of the Q-NANO initiative has been requested. This approach complements the outcomes of the project for the drilling approach. Protocols have been developed for samples identification and sharing considering the incorporation of RGU.

In relation to the protocols to be used for the mechanical degradation of the samples by drilling and crashing, a series of improvements have been considered necessary, having evaluated the protocols selected as a reference (NEPHH project). A series of optimizations have also been implemented on the test prototypes assuring environmental control and reproducible results.

B. Implementation Actions

B.1. Testing

Present task is divided into B.1.1. Nanocomposites subjected to physical processing for dust generation by drilling/crashing in ad hoc chambers; B1.2. Sample collection from the chambers; B.1.3. Physico-chemical characterization of the nano-fraction in generated dusts and B.4.1. Quantification of NPs released for Environmental Exposure Assessment.

So far, three project samples have been mechanically processed for particle release measurements via drilling. Airborne and deposited particles released in drilling processes have been collected and characterized. Mass balance of the released particles has been calculated for nano-release assessment. Additional experiments are actually in progress.

C. Monitoring the of the impact of the project actions

The monitoring actions for the period include: C.1. Identification of the specific indicators and sources of verification, C.2. Assessment of the initial situation – Value of the main indicators, and C.3. Monitoring actions. Actual values of the project impact indicators have been updated.

In the networking area (E.3) relevant contacts have been established at worldwide level; project results have also been transferred to the nanosafety community by means of the Nanosafety Cluster. Communication and dissemination actions (D), Project management and monitoring of the project progress (E)complete the work done up to date.