Polymers for Drinks Vending Applications
Submitting InstitutionUniversity of Manchester
Unit of AssessmentElectrical and Electronic Engineering, Metallurgy and Materials
Summary Impact TypeTechnological
Research Subject Area(s)
Chemical Sciences: Macromolecular and Materials Chemistry, Physical Chemistry (incl. Structural)
Engineering: Materials Engineering
Summary of the impact
Research at the University of Manchester has supported the development of
drinks vending systems for Mars Drinks. The research has demonstrated that
a detailed understanding of the relationship between the structure and
properties of the polymeric components is vital for the design and
performance of two drinks vending systems, Flavia (single-portion
fresh beverages) and Klix (in-cup beverages). This research has
contributed to major improvements in materials selection, quality control,
cost reduction and performance. These drinks vending systems were
developed originally in the UK in collaboration with the University of
Manchester, with Flavia now also manufactured in the USA and
marketed worldwide by Mars Drinks with an estimated sales value of >
US$400m per annum.
The research was undertaken by:
Professor Young throughout the period 1994-2013.
Dr Patrick Fairclough (PDRA, 1995-97).
Additional research students included William O'Kane (1993-1997), Craig
Meakin (1997-2001), Masakazu Tanaka (2001-2005) and Sylvain Rannou
The underpinning research has been undertaken though an EPSRC and
Mars-supported research programme in Manchester over the past 20 years.
Findings that have contributed to the impact in this area include:
Rapid crystallisation processes in polymer films [1,2].
Combined SAXS/WAXS on the Daresbury synchrotron was used to investigate
the mechanism for primary nucleation in polymer crystallization  as
previous research in this area had not been conclusive. Experiments on
polypropylene with long induction times, studied by small- and
wide-angle X-ray scattering (SAXS and WAXS), revealed the onset of
long-range ordering prior to crystal growth. Rapid crystallization
studied by melt extrusion indicated the development of well-resolved
oriented SAXS patterns associated with long-range order before the
development of crystalline peaks in the WAXS region. This highly-cited
research has led to a completely new insight into polypropylene
crystallisation that has enabled the rapid heat-sealing process in the
polypropylene films to be understood and fully characterised.
Characterisation of molecular orientation in polymer films
[3-5]. The properties of polymer films depend vitally upon the degree of
molecular orientation in the film. Polarised Raman spectroscopy is a
vibrational spectroscopic technique that is used widely for the chemical
and physical analyses of materials since it is both non-destructive and
suitable for remote analysis. Compared to other analytical techniques,
polarised Raman spectroscopy has the following advantages, (1)
quantitative and precise measurement of molecular orientation
distributions, and (2) study of these distributions in both the
crystalline and amorphous phases. It has been demonstrated that it is a
relatively rapid non-destructive technique that allows the properties of
polymer films to be characterised and related to their mechanical
Environmental stress cracking in high-impact polystyrene .
Polystyrene is a widely used polymer but is susceptible to environmental
stress cracking (ESC) in the presence of the fats in dairy products. It
was found that high-impact polystyrene with large rubber particles gave
the best ESC resistance . Moreover it was shown that processing of
the polymer into flat sheets by extrusion tends to damage and reduce the
size of the rubber particles, worsening the ESC resistance. It was
demonstrated that the appropriate choice of materials and processing
conditions enables the production of samples of polystyrene with improve
References to the research
The research has been published in leading international polymer journals
such as Macromolecules and Polymer and at the 14th
International Conference on Deformation, Yield and Fracture of Polymers,
the top international conference upon polymer properties. It also led to
Professor Young being awarded the 2012 Swinburne Medal and Prize of the
Institute of Materials, Minerals and Mining (IoM3), the premier
award of the Institute for research upon plastics.
1. `Simultaneous SAXS/WAXS and DSC Analysis of the Melting and
Recrystallisation Behaviour of Quenched Polypropylene', W.J. O'Kane, R.J.
Young, A.J. Ryan, W. Bras, G.E. Derbyshire, G.R. Mant, Polymer, 35
(1994) 1352-1358. (71 citations, WoS) DOI
2. `Density Fluctuations: The Nucleation Event in Isotactic Polypropylene
Crystallisation' N.J. Terrill, J.P.A. Fairclough, E. Towns-Andrews, B.U.
Komanschek, R.J. Young, A.J. Ryan, Polymer, 39 (1998)
2381-2385. (149 citations, WoS) DOI
3. `Polarised Raman Spectroscopy for the Study of Molecular Orientation
Distributions in Polymers', M. Tanaka, R.J. Young, Journal of
Materials Science, 41 (2006) 963-991. (31, WoS) DOI:10.1007/s10853-006-6595-7
4. `Molecular Orientation Distributions in the Crystalline and Amorphous
Regions of Uniaxially Oriented Isotactic Polypropylene Films Determined by
Polarized Raman Spectroscopy', M. Tanaka, R.J. Young, Journal of
Macromolecular Science-Physics, B44 (2005) 967-991. (3
citations, WoS) DOI:10.1080/00222340500323599
5. `Molecular Orientation Distributions in Uniaxially Oriented
Poly(L-lactic acid) Films Determined by Polarized Raman Spectroscopy, M.
Tanaka, R.J. Young, Macromolecules 39 (2006) 3312-3321.
(10 citations, WoS) DOI:10.1021/ma0526286
6. `Environmental Stress Cracking in High-Impact Polystyrene', S.A.D.
Rannou, R.J. Young, M. Tanaka, 14th International Conference on
Deformation, Yield and Fracture of Polymers, 6th-9th
April 2009, Kerkrade, The Netherlands. (pdf copy available on request)
Details of the impact
Mars Drinks is the drinks division of Mars Incorporated, a global company
with a turnover of over $33bn in Petcare, Chocolate, Wrigley, Food, Drinks
and Symbioscience. Mars Drinks was established in 1955, originally as the
Four Square Division of Mars, and now employs more than 650 Associates
across eight countries. Operating in the UK, France, Germany, USA and
Japan, Mars Drinks have their drinks machines in over 35,000 businesses
and produce more than one billion drinks a year with their two brands: Flavia
single portion fresh beverages; and Klix in-cup beverages [A]. A
conservative estimate would value sales at > US$400m per annum.
Polymers are used widely in the field of food packaging in the Mars group
and the Klix and Flavia both rely upon the performance of
their polymeric packaging and cups during the vending process.
Collaboration with the University of Manchester over many years has
enabled robust systems to be put in place to enable cost-effective and
reliable polymer-based systems to be specified. Since both types of drinks
are produced at the level of hundreds of millions per year, this gives
major challenges in terms of materials processing, performance, and
Pathways to Impact
The impact of the contribution of UoM to this project has been through
the evaluation of materials performance, quality control, trouble shooting
and helping direct materials specification. This has been undertaken
though Mars-funded research projects (£0.45 million over the 20-year
period) with the Manchester researchers working closely with the company
and with their suppliers, and spending time at the company premises.
Flavia freshly-vended drinks
A major achievement over the past 20 year period has been the
introduction of Flavia, which was originally only a European product, into
the export markets and more than double sales volumes [A]. Research
undertaken in the University of Manchester has had significant impact upon
the development of this product. Heat-sealing of the different
polypropylene components has been a major challenge and the fundamental
research undertaken upon the melting and crystallisation of polypropylene
has led to a detailed specification of the properties needed in the
different polypropylene components to produce a robust and reliable
system. For example, the problem of side bursts has now been reduced by
three orders of magnitude and so virtually eliminated. Consequently the Flavia
single portion fresh beverage system has revolutionised the delivery of
refreshments in the office environment. It is a simple to use, convenient,
clean and reliable drinks system that has replaced the "office coffee pot"
Klix instant drinks
The Klix system is now used widely in public spaces such as at
colleges and in factories, delivering a range of branded drinks, both
reliably and with consistent quality. The research at the University of
Manchester upon the material used in the Klix cups has been of
major significance in the development of the system. Topics studied have
included polymer blends, rubber toughening, thermal conductivity and
recycling. A specific example of impact was in solving the problem of
environmental stress cracking (ESC) in the high-impact polystyrene (HIPS)
cups used in the Klix system — a potential safety hazard.
Polystyrene is susceptible to ESC in the presence of the fats in dairy
products. This was found to be a particular issue for the Klix
system with milky drinks such as drinking chocolate or white coffee. It
was demonstrated that the ESC problem resulted from the size and form of
the rubber particles in the grade of HIPS employed in the presence of
dairy products. The relatively small rubber particles in HIPS were
susceptible to damage during processing that reduced their effective size
further. It was found that the ESC problem could be overcome by specifying
a different grade of HIPS with larger rubber particles.
The underpinning research with the University of Manchester, that has led
to the development of the present Klix and Flavia drinks
systems has been a central and necessary component in the success of Mars
Drinks [A] through:
- Better materials selection
- Improved quality control
- Improvements in packaging performance
- Significant cost reduction
One particular problem that was encountered before the collaboration with
the University of Manchester was that the polymer-based components in Flavia
and Klix were poorly specified in terms of their structure and
properties, which meant that company was susceptible to changes in grades
of polymer by their suppliers. This research has had significant impact in
the areas of materials selection and quality control, coupled with an
improvement in performance and an associated significant cost reduction.
Sources to corroborate the impact
[A] Letter Packaging Manager at Mars Drinks confirming the role of the
research in the development of the Flavia® and Klix®
range of drinks and the doubling of sales volume this produced.