Frequently Asked Questions
TonerPlas is a polymer compound that increases asphalt longevity. It is used as a dry mix additive to modify the binder
and will improve the mechanical properties of asphalt, by reducing flow and deformation and imparting elasticity in
the bituminous binder mastic.
TonerPlas is a manufactured polymer compound – it is not raw waste plastic.
TonerPlas is formulated on a mixture of post-consumer soft plastics and toner (from print industry). Note: toner is a
powdered coloured polymer
Technical perspective: the polymers in mixed soft plastics are better suited to binder modification because they have
a low melting point and better elasticity than conventional hard plastics.
Environmental Perspective: Flexible packaging is the fastest growing packaging group with the lowest recycling rate.
Soft plastics are not represented in the kerbside recycling stream, and approximately 450,000 tonne are landfilled in
Australia per year (and growing).
No, we only use post-consumer mixed soft plastics from the Redcycle (www.redcycle.net.au) and other similar
programs. These plastics have very few recycling options because it’s not possible to separate by polymer type, and
they could contain food residues and other contaminants. NB. Close the Loop’s advanced manufacturing line first
removes contaminates before shredding, blending, melting, mixing, adding other recycled ingredients of value, and
finally pelletising the finished product.
No. Your kerbside collection is for rigid plastics which are all recyclables with existing end markets. Some rigid plastics
are often not compatible with bitumen and would simply act as a filler. TonerPlas is a performance enhancing additive
and the environmental benefits are huge but secondary.
The Close the Loop laboratory is equipped for developing polymer compounds and rheological characterisation (flow
behaviour testing by DSR). CtL specialises in comprehensive asphalt binder testing, to understand and characterise
the effects of its asphalt additives. For asphalt performance testing, we rely on the partnership of an asphalt company
that has a fully equipped asphalt performance test lab.
The dry mix method: TonerPlas is designed for direct addition to an asphalt mix plant – continuous drum or batch
plant. It is intended to be added with the bitumen and mixed with the preheated aggregate in one stage.
It is fed into the asphalt plant via the additive feed line. This method avoids the expense of pre blending with
bitumen in a separate process.
No. TonerPlas is designed to blend and homogenise into the asphalt and binder matrix under standard asphalt mix
conditions. TonerPlas is suitable for both hot and warm mix.
Tonerplas was designed to enhance conventional bitumen such as C170 and C320. It was not designed to replace PMB
grades. In some cases TonerPlas may be used to offset a percentage (in the region of 10%) of PMB grades for state
road applications – this is an area of ongoing study and product development.
No. TonerPlas is designed to be used with the binder chosen for a particular mix design. It will increase the softening
point and enhance elasticity, without significantly affecting low temperature modulus / stiffness. In C170 and C320
bitumen, TonerPlas will significantly enhance the viscoelastic properties.
When TonerPlas is introduced into the asphalt mix, it melts and homogenises with, and becomes part of the binder
matrix. Like other polymer modified binders (SBS and EVA), the polymers in TonerPlas are thermoplastic and will remelt in the binder matrix when RAP is reprocessed. The presence of polymer modified binder in the RAP does not
necessitate changes to the RAP processing procedures. RAP with TonerPlas is processed as per ‘AAPA Reclaimed
Asphalt Pavement (RAP) Management Plan’.
https://www.aapa.asn.au/wp-content/uploads/2018/06/AAPA-RAP-Management-plan-12-June-2018.pdf
Due to its effect of increasing binder viscosity, TonerPlas may affect workability. Adjustment of the mix design may
be required depending on the amount used and other mix design factors.
Every 1 km of road* paved with TonerPlas modified asphalt uses approximately:
- 530,000 plastic shopping bag equivalents
- Waste toner from 12,500 printer cartridges
* Top layer wearing course of a standard two lane suburban road
The infeed raw materials are characterised and from known sources.
The advanced manufacturing process ensures that the end product is of a highly consistent nature. During production,
TonerPlas is sampled daily and QC tested for critical physical properties that characterise its viscoelasticity, to ensure
that its behaviour in asphalt is consistent and predictable.
No, the NSW EPA have recently approved an Order & Exemption (O&E) for Reconophalt, the Downer asphalt
including TonerPlas. The O&E states that the Reconophalt road, including TonerPlas, poses no more risk of
microplastics and leachate than a standard asphalt road. The NSW EPA conducted the harshest test regime ever
seen in the Australian roads industry to complete this report. You can download a copy here:
https://www.downergroup.com/Content/cms/media/2020/Documents/The_Downer_bituminous_pavement_order
_and_exemption_2020.pdf
Leachate was also tested and shown to be no more of a risk when using TonerPlas than from a standard asphalt road.
Tonerplas is considered to be very stable and of low fume potential at normal processing temperatures of asphalt, at
around 160’C. The soft plastics used to make Tonerplas is predominately from food and retail packaging.
It’s important to note that TonerPlasis a melt processed polymer compound, not raw unprocessed plastics. The infeed
soft plastics (predominately LDPE) have gone through a process of shredding, cleaning, melting and blending to
ensure thorough homogenisation. During the initial processing stage, the soft plastics are processed at high
temperature so any volatile compounds are evolved during this stage, along with residual moisture.
Further hot compounding at a lower temperature, blends in the toner and oil to create the final TonerPlas compound.
The other factor is concentration in asphalt, where TonerPlas only exists as a minor component up to 0.75%, therefore
based on concentration alone, its contribution to asphalt fumes and odour is very minor.
Past experience by many asphalt plants and paving crews around Australia, including air monitoring, has demonstrated
no issues around fuming with regards to asphalt containing TonerPlas
There are no existing standards for plastics use in asphalt. Current asphalt mix designs are material specific and
design specific. TonerPlas is an innovation that sits outside of the current prescriptive specification framework for
asphalt mix designs.
For asphalt mixes containing TonerPlas, asphalt manufacturers can register new ‘conditional mix designs’ with state
DOT’s. Once a ‘conditional mix design’ is approved and registered, it can be specified for jobs.
Yes. Please email your local council name to steve@closetheloop.com.au and the reason you want the information,
and we’ll get a report to you by email.
For TonerPlas technical enquiries, please contact:
• Dave Hitzler (Tech Manager) – dhitzler@closetheloop.com.au
For TonerPlas sales enquiries, please contact:
• Steve Morriss at steve@closetheloop.com.au