Construction Manual for Polymers + Membranes

296 Pages·2011·31.151 MB·English

by  Jan Knippers, Jan Cremers, Markus Gabler, Julian Lienhard

Construction
Manual for
Polymers +
Membranes
MATERIALS
SEMI-FINISHED PRODUCTS
FORM-FINDING
DESIGN
KNIPPERS
CREMERS
GABLER
LIENHARD
Birkhäuser Edition Detail
Basel Munich
Authors Specialist articles:
Joost Hartwig, Dipl.-Ing.; Martin Zeumer, Dipl.-Ing. (Environmental
Jan Knippers, Prof. Dr.-Ing. impact of polymers)
Institute of Building Structures & Structural Design (itke) Field of Study Design & Energy-Efficient Construction, Department of
Faculty of Architecture & Urban Planning, University of Stuttgart Architecture, Technische Universität Darmstadt
Jan Cremers, Prof. Dr.-Ing. Architect Carmen Köhler, Dipl.-Ing. (Natural fibre-reinforced polymers and
Faculty of Architecture & Design biopolymers)
Hochschule für Technik Stuttgart Institute of Building Structures & Structural Design (itke),
Faculty of Architecture & Urban Planning, University of Stuttgart
Markus Gabler, Dipl.-Ing.
Institute of Building Structures & Structural Design (itke) Consultants:
Faculty of Architecture & Urban Planning, University of Stuttgart Christina Härter, Dipl.-Ing. (Polymers)
Institute of Polymer Technology (IKT), University of Stuttgart
Julian Lienhard, Dipl.-Ing.
Institute of Building Structures & Structural Design (itke) Andreas Kaufmann, MEng (Complex building envelopes);
Faculty of Architecture & Urban Planning, University of Stuttgart Philip Leistner, Dr.-Ing. (Building physics and energy aspects)
Fraunhofer Institute for Building Physics (IBP), Stuttgart/Holzkirchen
Assistants:
Sabrina Brenner, Cristiana Cerqueira, Charlotte Eller, Manfred Hammer, Alexander Michalski, Dr.-Ing. (Loadbearing structure and form)
Dipl.-Ing.; Petra Heim, Dipl.-Ing.; Carina Kleinecke, Peter Meschendörfer, Chair of Structural Analysis, Technische Universität Munich
Elena Vlasceanu
Mauricio Soto, MA Arch. (Building with textile membranes)
studio LD
Jürgen Troitzsch, Dr. rer. nat. (Building physics and energy aspects)
Fire & Environment Protection Service, Wiesbaden
Editorial services Bibliographic information published by the German National Library.
The German National Library lists this publication in the Deutsche
Editors: Nationalbibliografie; detailed bibliographic data are available on the
Judith Faltermeier, Dipl.-Ing. Architect; Cornelia Hellstern, Dipl.-Ing.; Internet at http://dnb.d-nb.de.
Jana Rackwitz, Dipl.-Ing.; Eva Schönbrunner, Dipl.-Ing.
This work is subject to copyright. All rights reserved, whether the whole
or part of the material is concerned, specifically the rights of translation,
Editorial assistants:
reprinting, recitation, reuse of illustrations and tables, broadcasting, re-
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ing systems. Reproduction of any part of this work in individual cases,
too, is only permitted within the limits of the provisions of the valid edi-
Drawings:
tion of the copyright law. A charge will be levied. Infringements will be
Dejanira Ornelas Bitterer, Dipl.-Ing.; Ralph Donhauser, Dipl.-Ing.;
subject to the penalty clauses of the copyright law.
Michael Folkmer, Dipl.-Ing.; Marion Griese, Dipl.-Ing.;
Daniel Hajduk, Dipl.-Ing.; Martin Hämmel, Dipl.-Ing.;
This book is also available in a German language edition
Emese Köszegi, Dipl.-Ing.; Nicola Kollmann, Dipl.-Ing. Architect;
(ISBN 978-3-920034-41-6)
Simon Kramer, Dipl.-Ing.; Elisabeth Krammer, Dipl.-Ing.
Publisher:
Translation into English:
Institut für internationale Architektur-Dokumentation
Gerd H. Söffker, Philip Thrift, Hannover
GmbH & Co. KG, Munich
www.detail.de
Proofreading:
James Roderick O’Donovan, B. Arch., Vienna (A)
© 2011 English translation of the 1st German edition
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4
Contents
Preface 6 Part E Building with polymers and
membranes
Part A Polymers and membranes in 1 B uilding with semi-finished
architecture polymer products 160
2 Building with free-form polymers 174
The discovery and development 3 Building with foil 188
of polymers 10 4 Building with textile membranes 196
The dream of the polymer house 12 5 Complex building envelopes 212
Development of tensile surface structures 16
Structures with transparent and
translucent envelopes 21 Part F Case studies
Potential, trends and challenges 24
Examples 1 to 23 225
Part B Materials
Part G Appendix
1 Polymers 30
2 Fibres 48 Statutory instruments, directives,
3 Adhesives and coatings 54 standards 286
4 Natural fibre-reinforced polymers Bibliography 287
and biopolymers 60 Authors 289
Picture credits 290
Abbreviations for polymers 292
Part C Semi-finished products Index 292
Index of names 295
1 Primary products 68
2 Fibre-reinforced polymers 76
3 Semi-finished polymer products 82
4 Foil 94
5 Textile membranes 100
6 Building physics and energy aspects 108
7 Environmental impact of polymers 124

Part D Planning and form-finding
1 Loadbearing structure and form 134
2 Detailed design aspects 150
5
Preface
Whereas building with textiles can look back In keeping with the tradition of the Construction
on thousands of years of tradition, plastics, or Manuals series, this volume is devoted to the
rather polymers, represent a comparatively new applications of polymers that shape architecture,
class of materials. So in that respect at first and that includes loadbearing structure, building
glance it might surprise the reader to discover envelope and interior fitting-out. Descriptions of
both topics combined in one book. But this ap- the common material principles – from the twin-
proach is less surprising when we consider the wall sheet to the coated glass-fibre membrane
fact that it was not until the middle of the 20th – run through this book like a common thread. The
century that membranes first found their way into parallels within the group of synthetic materi als
architecture – as synthetic fibres and polymer are pointed out in every chapter, emphasized
coatings en abled the production of more dura- irrespective of the differences in the construc-
ble, stronger textiles, which replaced the cotton tional realisation and architectural application.
cloth that had been used for tents up until that It is this approach that distinguishes this publi-
time. It was the development of modern syn- cation because it is more customary to deal with
thetic materials that helped Frei Otto, Walter building with textiles and building with polymers
Bird and others to build their pioneering tensile separately.
surface structures, which quickly attracted
attention and became widespread over the fol- What all synthetic materials have in common is
lowing decades. that they exhibit an extremely wide range of
properties. By choosing a suitable raw material
At first, plastics were developed to provide sub- and modifying it during production and the
stitutes for valuable and scarce natural resources subsequent processing stages, it is possible to
such as ivory, shellac or animal horn, or to re- match a material or product to the respective
place less durable materials such as cotton. requirements very precisely. Such options are
Since the early 1950s, synthetic materials have very often available to the designer, but not al-
been taking over our daily lives, symbolising ways. Part B “Materials” therefore first describes
the dream of a happy future brought about by the basic materials, i.e. primarily polymers and
technical progress. But the public’s opinion of fibres, and their production and processing
polymers started to change quite drastically to- technologies in detail. In doing so, the authors
wards the end of the 20th century. The reasons have attempted to bridge the gap between the
for this were the defects frequently encountered polymers familiar from everyday use and the
with polymers used for buildings and the rising highly efficient polymers employed in the con-
costs, but particularly a growing environmental struction industry. These processes are intrinsic
awareness in which synthetic materials no to an understanding of semi-finished products
longer seemed to play a part. Consequently, and forms of construction involving synthetic
as the historical review in Part A “Polymers and mater ials. The information goes well beyond
membranes in architecture” shows, the true the current state of the building art in order to do
polymer house has not enjoyed any success so justice to the dynamic developments in this
far. field. For example, materials researchers are
By contrast, the spread of the materials them- currently intensively involved in the search for a
selves throughout the world of everyday artefacts, substitute for oil-based polymers in order to
likewise the building industry, has proceeded reduce the consumption of finite resources and
almost unnoticed. This is why polymers are now allow better recycling of end-of-life materials.
to be found everywhere in buildings, albeit less Natural fibre-reinforced polymers and biopoly-
in visible applications and more in the technical mers therefore have a chapter all to themselves,
and constructional make-up of a building; seals, even though these materials are of only sec-
insulation, pipes, cables, paints, adhesives, coat- ondary importance in the building industry at
ings and floor coverings would all be inconceiv- present and really only play a role in the auto-
able these days without polymers. motive and packagings sectors.
6
The plastics and textile industries make use of membrane structures, however, calls for totally was required for this book. We would therefore
specific technologies for the step from primary different procedures to those we are used to like to thank all those who have supported us:
to semi-finished product, technologies that are with other building materials. A profound under- the consultants from various sectors, the stu-
otherwise unknown in the world of construction. standing of the relationship between force and dents who prepared the drawings and the
Those technologies include very diverse aspects form is crucial here, and this aspect is dealt photog raphers of the University of Stuttgart’s
such as the processing of fibres to form textiles, with fully in a separate chapter. Werkstatt für Photographie.
the foaming of polymers and also processes like
extrusion and injection-moulding. Following a Practical and descriptive presentations of build- The idea of bringing together polymers and
general review of primary products, Part C “Semi- ing with semi-finished and free-form polymer membranes in one book is not only reflected in
finished products” takes separate looks at rein- products, also foils and textile membranes can the title. The joint work on the chapters by all
forced and unreinforced polymers as well as all be found in Part E “Building with polymers the authors led to a tight interweaving of the
films (often called foils) plus coated and uncoated and membranes”, which for the first time con- diverse fields of knowledge. This Construction
textiles. One special characteristic of all polymers tains a detailed overview of design solutions. It Manual closes a gap in the specialist literature.
is that not only their mechanical, but also their is not just the building technology aspects that We very much hope that it will contribute to an
building physics properties, e.g. permeability to are investigated here, but also the significance increased interest in these materials and, above
light and heat, can be adjusted very specifically. of the materials in the building envelope in terms all, to new applications in architecture.
The ensuing options are explored in detail. of building physics, which explains the attention
The chapter covering the environmental impact given to the options of multi-layer and multi-leaf The authors and publishers
of polymers is a response to the very emotional forms of construction. August 2010
debate about the ecological characteristics of
synthetic materials. In the form of insulating and The projects selected for Part F “Case studies”
sealing materials, polymers in many cases make primarily comply with the criterion of an exem-
an indispensable contribution to ecologically plary integration of polymers or membranes in
efficient building design, and their low weight a way that influences the architecture. The aim
means they have the potential for creating light- was to present a wide selection of building types
weight structures that use their building materials and locations.
efficiently. The disadvantages, however, are the The case studies show that many possibilities –
high energy input required during production, the integration of functions for redirecting day-
the extensive use of fossil fuels and the unsatis- light, generating energy or storing heat, to name
factory recycling of these materials once their but a few – are currently not exploited at all in
useful lives have expired. This chapter makes it buildings or at best are in their early days.
clear that ecological assessments of construc- Technologies already familiar in the automotive
tions made from polymers can have very differ- or aircraft industries, e.g. “smart” structures made
ent outcomes depending on the raw materials, from fibre composites with integral sensors and
the constructional realisation and the architec- actuators, have not yet found their way into the
tural function, and that global statements on construction sector. There is great potential here
this subject are impossible. which will open up many possibilities in archi-
tecture. The development of synthetic materials
Part D “Planning and form-finding” illustrates the is progressing apace. In order to do justice to
similarities, but also the differences, between this fact, the latest results from research, some
the various uses of polymer materials. The struc- of them not yet published, have been incorp -
tural analysis of tensile surface structures and orated in the writing of this book.
rigid polymer designs is normally handled in
totally separate codes of practice and regula- In the past the publications available on poly-
tions. However, this comparative presentation mers have been limited to very specific works
shows that the principles shared by the materi als of reference, e.g. for aviation or mechanical
and the resulting similarity between the creep engine ering. A compilation of the principles of
and fatigue strength behaviour lead to related the materials with respect to applications in
analysis concepts, even when the constructional architecture has not been undertaken so far,
realisation is totally different. Form-finding for which is why a great deal of preparatory work
7

Part A Polymers and
membranes in architecture
The discovery and development
of polymers 10
From alchemy to chemistry 10
Polymer chemistry and industrial production 11
Polymers in furniture and industrial design 11
The spread of polymers 12
The dream of the polymer house 12
First buildings of glass fibre-reinforced
polymer (GFRP) 13
The polymer module for the house of
tomorrow 13
Plastic houses as an expression of
visionary ideas 14
Building with polymers and the
first oil crisis 14
Room modules made from polymers –
industrial prefabrication and batch
production 14
Polymers today 15
Development of tensile surface structures 16
The lightweight tensile surface structures
of Frei Otto 16
Pneumatic structures 17
Cable nets and membrane roofs for sports
stadiums 19
Tensile surface structures in contemporary
architecture 20
Materials in membrane architecture –
from natural to synthetic fibre fabrics
and polymer foil 20
Structures with transparent and
translucent envelopes 21
Potential, trends and challenges 24
Applications and potential 24
Trends and developments 25
Challenges 27
Fig. A Mobile membrane pavilion, Stuttgart (D), 2006,
Julian Leinhard
9
Polymers and membranes in
architecture
A 1
The discovery and development of polymers suitable solvent and binder that would turn the
nitrocellulose fibres into a workable polymer
Wood rots, metals are expensive, leather be- compound. Alexander Parkes presented a pre-
comes brittle and horn warps! Humankind has cursor, so-called Parkesine, at the 1862 World
for a long time been dreaming of replacing nat- Exposition in London. However, owing to the
ural materials by synthetic ones that are easy to rapid formation of cracks it was not successful.
produce and work, long-lasting and readily It was the American book printer John Wesley
available to everyone. Hyatt who finally developed the technical meth-
It was this dream that tempted the alchemists od for producing celluloid by using camphor as
of past centuries to engage in the weirdest of a solvent. He applied for a patent for his method
experiments. With some success: in the Arabic in 1870. This form of celluloid quickly became
world they distilled blossoms to make perfumes, popular and was used not only for billiard balls,
in China they invented gunpowder and paper. A but also as an imitation for mother-of-pearl, tor-
synthetic resin – obtained by repeated boiling toiseshell and horn for combs and hair acces-
of low-fat cheese and used for medallions and sories, and for toys, spectacles, toothbrushes,
cutlery – was produced in Augsburg in southern false teeth and, ultimately, for films. George
Germany as long ago as the 16th century. One Eastman, the founder of the Kodak company,
of the last great successes of the European started producing roll film made from celluloid
alchemists was the discovery of porcelain. After in 1889 and thus made photography accessible
much experimentation, they finally managed to to the masses.
produce that “white gold” in Meissen in former By the end of the 19th century, manufacturers
East Germany in the 18th century – more than urgently needed a substitute for another expen-
1000 years after China had done it! sive natural product associated with a very costly
production method: silk. It was the French scien-
From alchemy to chemistry tist Hilaire de Chardonnet who managed to pro-
The change from practical alchemy to theoret- duce an artificial silk based on cellulose. But,
ical chemistry took place gradually with the rise although this marked the beginning of the pro-
of the natural sciences in the 17th and 18th duction of synthetic fibres, this form of artificial
centuries. And chemistry became a key science silk brought no long-term success because, like
of the Industrial Revolution in the 19th century: all products made from cellulose, it suffered
the mass production of textiles called for new from the serious disadvantage of being highly
dyes as well as detergents and bleaching flammable.
agents, foundries were looking to improve the
production of metals, mines needed effective Soon after this the Swiss chemist Jacques
and safe lamps. Replacements for scarce and Brandenberger managed to produce an ultra-
expensive natural materials such as ivory, horn, thin transparent foil: cellophane, which is still
shellac, coral and silk were urgently required, used today for packaging.
and so the first steps on the road to modern In order to replace shellac, a resin-like substance
synthetic materials were taken. The offer of a that is obtained in a laborious process from the
prize of US$ 10 000 to the first person who secretions of the lac bug (kerria lacca) and
could produce billiard balls from a synthetic therefore very expensive, the Belgian chemist
replacement for ivory apparently provided the Leo Baekeland developed the first completely
A 1 Hermann Staudinger explaining his molecular chain impetus for the development of celluloid. man-made substance made exclusively from
theory on which modern polymer chemistry is
The basic ingredient of celluloid is cellulose, the synthetic raw materials around 1905: Bakelite.
based.
A 2 The cover of the first issue of Kunststoffe (plastics), natural polymer that gives plants their stability. The main constituent of Bakelite is phenol, a
Munich, 1911 Adding a mixture of nitric and sulphuric acid al- waste product of coke production which is con-
A 3 Radio with Bakelite case, Philips, 1931 ters the consistency of the cellulose and pro- sequently very cheap. Bakelite is an electrical
A 4 “Jumo Brevete” desk lamp, France, c. 1945
duces nitrocellulose, the raw material required insulator and only ignites above a temperature
A 5 “Rocking Armchair Rod” (RAR) from the Plastic Shell
for the production of celluloid. However, it took of 300 °C. It therefore proved to be suitable as
Group, 1948, Charles and Ray Eames
A 6 Stacking chair, 1960, Werner Panton a long time and many experiments to find a a shellac substitute and was used primarily as
10
Polymers and membranes in architecture
A 2 A 3
a thin layer of insulation in the first electrical able clothing, were used for parachutes. The
devices. At last the electrical engineering in- polyester fibres so important for membrane
dustry had the insulating material it had been structures these days were developed in Eng-
searching for. Bakelite thus rendered possible land by J. R. Whinfield and J. T. Dickinson in
the mass production of switches, ignition coils 1940 and given the trade name “Trevira”, also
and radio and telephone equipment (Fig. A 3, originally intended for clothing.
see also “Phenol formaldehyde, phenolic resins”,
p. 46). The oldest of the mass-produced polymers used
these days is polyvinyl chloride, or PVC for short.
Polymer chemistry and industrial production Fritz Klatte, a researcher at the Griesheim-Elektron
The German term for polymers or synthetic mater- chemicals factory near Frankfurt am Main, pa-
ials, Kunststoffe, was used for the first time in tented a method for producing PVC as early as
1911, as the title of a trade journal, and estab- 1912. PVC was intended to replace the highly
lished itself in the following years (Fig. A 2). flammable celluloid. However, the outbreak of
However, the scientific basis for the production the First World War delayed the introduction of
of polymers – polymer chemistry – was first de- large-scale industrial production of PVC and it
veloped in the early decades of the 20th century was not until the 1930s that this polymer could A 4
by Hermann Staudinger, professor of chemistry be mass produced for cable sheathing, pipes
in Freiburg and Zurich (Fig. A 1). It was for this and numerous other commodities.
work that he was awarded the Nobel Prize in The majority of polymers appeared in quick
1953. succession in the middle of the 20th century:
In the early years the manufacture of celluloid, • Polymethyl methacrylate (PMMA, acrylic
Bakelite and related materials was based on sheet), 1933
experience, speculation and chance. But a scien- • Polyethylene (PE), 1933
tific basis rendered possible a fully focused • Polyurethane (PUR), 1937
development of synthetic materials: research • Polyamide (PA), 1938
into chemistry was transformed from experiments • Unsaturated polyester (UP), 1941
by creative individuals into strategically planned • Polytetrafluoroethylene (PTFE, Teflon), 1941
projects in large research departments. One • Silicone, 1943
example of the latter is nylon, the first completely • Epoxy resin (EP), 1946
synthetically produced and commercially ex- • Polystyrene (PS), 1949
ploited synthetic fibre. It is made from cold-drawn • High-density polyethylene (PE-HD/HDPE),
polyamide and was the result of 11 years of re- 1955
search by the American chemicals group Du- • Polycarbonate (PC), 1956 A 5
Pont. Led by Wallace Hume Carothers, who had • Polypropylene (PP), 1957
succeeded in producing neoprene, a synthetic • Ethylene tetrafluoroethylene (ETFE), 1970
rubber, while working at DuPont in 1930, a
230- strong team was involved in the develop- Polymers in furniture and industrial design
ment of this synthetic fibre. When nylon was Polymers are not even 100 years old – a great
launched onto the market in 1938, it was initially contrast to many of the other materials com-
in the form of bristles for toothbrushes and later monly used in the building industry. But the d
for ladies’ stockings. The first four million pairs esign options of these new materials were very
of stockings were sold within a few hours of quickly discovered and so it was not long be-
their appearance in New York stores in 1940! fore they became part of everyday building
Working independently, a team at the I.G.-Far b en practice. Shapes that had been impossible in
industrie AG plant in Berlin succeeded in pro- the past were now added to the vocabulary of
ducing a polyamide fibre with a very similar industrial and furniture designers. Examples of
structure in 1939; they called their product this include the French desk lamp “Jumo Brevete”
“Perlon”. During the Second World War, these of 1945 made from Bakelite (Fig. A 4), or the
synthetic fibres, originally created for fashion- range of foodstuffs containers made from
A 6
11
Plastics and membranes in architecture
A 7 A 8 A 9
moulded thermoplastic polyethylene launched hollow inside. With their firm but detachable polymers when the price of their raw material
in 1946 by the Tupper Plastics Company, connections and production by means of injec- starts to rise steeply. It is therefore likely that the
founded by former DuPont chemist Earl S. tion moulding, these bricks were a far cry from development of biopolymers from renewable
Tupper. In furniture the first really significant wooden building blocks. By 1958 hollow tubes raw materials will become more and more im-
use of polymers for mass-produced articles had been incorporated inside to stabilise the portant (see “Biopolymers”, pp. 62 – 65). For
began in 1948 with the seat shells of moulded, connection between the bricks. That distinguished example, polylactic acid (PLA) polymers made
glass fibre-reinforced polyester designed by them even more so from the familiar options for from lactic acid are already in wide use in the
Charles and Ray Eames and marketed by the fitting wooden blocks together. packaging industry. Although the market share
Plastic Shell Group (Fig. A 5, p. 11). Irwine and The properties of the material itself were also is currently under 1 %, it is growing rapidly.
Estelle Laverne designed their “Champagne optimised: since 1963 LEGO bricks have been So, whereas the first polymers were made from
Chair” in 1957, with a seat shell of transparent, made from the copolymer acrylonitrile butadiene natural cellulose and the transition to synthetic
moulded acrylic sheet. They were inspired by styrene (ABS). materials based on oil took place only gradually,
the architect and designer Eero Saarinen, who The example of the LEGO brick shows quite 100 years later our newly acquired awareness
two years previously had designed his “Tulip clearly that being able to adjust the material of the finite nature of the earth’s resources is
Chair”. Perhaps the most important piece of properties when designing the material plus triggering a reversal of this process.
polymer furniture ever, the stacking chair, first moulding options can open up totally new con-
appeared in a design by Werner Panton in 1959 figuration and jointing possibilities that go way
(Fig. A 6, p. 11). It was the first chair made from beyond those of conventional materials. The The dream of the polymer house
just a single material – rigid polyurethane foam huge popularity of building kits made from poly-
(from 1970 onwards made from the styrene mers (many others as well as LEGO) led to scores During the Second World War, industry was
thermoplastic ASA/PC, later polypropylene; see of people being subconsciously confronted producing goods almost exclusively for the
also “Thermoplastic moulded items”, p. 91) – with construction options from a very early age armed forces. This situation had an effect on the
using injection moulding and just one mould. It with constructions options other than those of emerging polymers industry – polymer production
was in 1962 that Robin Day devised the “Poly- classical building forms and materials. was mainly confined to parachutes, polyethylene
prop”, an extremely low-cost chair with the first cable sheathing for radar systems and light-
polypropylene injection-moulded seat shell and The spread of polymers weight, scratch-resistant polycarbonate turrets
legs made from bent steel tubes; some 14 million Polymers are these days ubiquitous and produced and cockpits for bombers. To achieve this,
of these chairs have been sold since 1963! in huge quantities. For example, bottles made production capacities had to be stepped up
Polymers were increasingly opening up new from polyethylene terephthalate (PET) have very quickly: in the USA 5000 sheets of poly-
options thanks to the great flexibility of their been in widespread use since the mid-1990s. carbonate were being produced every month
material properties and the emergence of new Returnable, reusable PET bottles, which are in 1937, but by 1940 the number had risen to
production methods (e.g. polymer injection mould- only about one-twelfth the weight of comparable 70 000!
ing), which also permitted new, more economic glass bottles, can be returned and refilled about After the war, these capacities were available
jointing principles to be used – a not insignificant 10 times before they have to be reprocessed for non-military uses once again. The search for
factor. This process of expanding design and (approx. 40 reuses for glass bottles). Worldwide new markets helped polymers to gain a foot-
construction options, which would later become annual PET production amounts to approx. hold in all aspects of everyday life. For example,
so important for the building industry, too, can 40 million tonnes (2007), which accounts for about huge numbers of ladies’ stockings could be
be seen in the development of the LEGO build- one-fifth of all polymers produced, and more produced for the market; the onslaught on
ing bricks system, which began life in the mid- than 125 million PET bottles were produced in American department stores when “nylons”
20th century. Ole Kirk Christiansen, a Danish 2003. The reuse rate, i.e. the proportion of re- finally became available again in the autumn of
joiner who actually made wooden toys, was in- cycled PET bottles as a percentage of the total 1945 is legendary. Stockings, clothes and under-
spired by the children’s building kit “Kiddicraft quantity in circulation, was, for instance, 78 % in wear made from nylon, Perlon or Trevira be-
Self-Locking Building Bricks” (for which the Switzerland in 2008 (more than 35 000 t, or more came incredibly popular in the post-war years.
Englishman Harry Fisher Page had been granted than one billion bottles). And household goods and packagings made
a patent) and began producing very similar The price of the main resource required for the from polyethylene or polypropylene were now
building bricks in 1949, selling them under the production of polymers, i.e. petroleum, has so suddenly appearing in every kitchen. As poly-
name of “Automatic Binding Bricks”, and from far remained comparatively low, a fact that has mers proved successful for everyday items and
1953 onwards under the LEGO brand. The first contributed to the enormous spread of polymer were already being used for furniture, too, it
bricks were made from cellulose acetate, with products throughout the world. But for the future seemed obvious to use them for buildings as
the well-known studs on the top but completely we must ask ourselves how we wish to handle well.
12