Polyurethane raw materials and sys - PUR-Internet - Bayer

Collective know-how
for automotive
engineering
Bayer AG
Polyurethanes Business Group
Bayer on the Internet: http://www.bayer.com D-51368 Leverkusen
This information and our technical advice – whether verbal‚
in writing or by way of trials – are given in good faith but
without warranty‚ and this also applies where proprietary
rights of third parties are involved. Our advice does not
release you from the obligation to verify the information
currently provided – especially that contained in our safety
data and technical information sheets – and to test our
products as to their suitability for the intended processes
and uses. The application‚ use and processing of our
products and the products manufactured by you on the
basis of our technical advice are beyond our control and‚
®
Bayer’s cross-disciplinary approach to developments in automotive engineering involves all our
relevant product lines: rubber, thermoplastics, coating raw materials, polyurethanes and other
high-grade products from Bayer range.
This pooling of our resources forms the basis of Bayer’s “Auto creative“ initiative. At once a
challenge and a promise, it means harnessing all our know-how, experience and creativity for
the benefit of the automotive industry.
therefore‚ entirely your own responsibility. Our products are
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Conditions of Sale and Delivery.
The methods described in this publication for testing the
fire performance of polyurethane‚ and the results quoted‚
do not permit direct conclusions to be drawn regarding every
possible fire risk there may be under service conditions.
Order no.: PU 52 220e · Edition: 10.98
Printed in Germany · E
Polyurethane raw materials and systems
from Bayer. Driving ahead in
automotive engineering.
Collective know-how
for automotive
engineering
®

Polyurethane - the material for
automotive engineering
With an annual worldwide consumption of
approx. 1 million tonnes, polyurethane is one of
the most widely used groups of plastics in automotive
engineering. An average of approx. 18 kg is
used in each vehicle, with up-market models containing
even greater amounts. Polyurethanes are not just
commodity plastics. They are manufactured from
polyurethane raw materials and systems, from which
the processors themselves produce tailor-made
articles to meet their individual requirements.
The increasing number of polyurethane applications
in cars can be attributed to their special combination
of product properties:
� Low-cost component manufacturing and
vehicle assembly
� Excellent long-term performance characteristics
coupled with light weight
� Improved comfort and model differentiation
� Increased safety reserves in the event of accidents
� Resource conservation through lightweight construction
and recycling
Bayer –
a dependable
partner worldwide
Today, Bayer is the world's largest
supplier of polyurethane
raw materials and engineering
polyurethanes for the automotive
sector. Bayer is a dependable
and resourceful partner in the
supply of raw materials and
systems, the development of
manufacturing technologies and the optimisation of
components both for globally operating automotive
companies and suppliers and for local, mid-sized
companies. Development, marketing and production
are located close to the local processors, but are linked
to a global network.
Worldwide polyurethane consumption in the automotive industry
(Status: 1998)
2 3
1.200
1.000
800
600
400
200
0
in Tausend 1,000 tonnes
Tonnen
Marketing centres with integrated technical service centre
Technical Marketing centres service with integrated centres technical service centres
Technical service centres
Production sites sites including - incl. machinery processing and processing machinery technology fromand
equipm
of our our subsidiary affiliated Hennecke company GmbH Hennecke GmbH
Bayer has marketing centres, technical service centres
and production sites all over the world: in Europe,
in the NAFTA region, in South America and the Far
East. Nearness to the customer enables us to focus on
local market needs.
1990 91 92 93 94 95 96 97 98 99 2000 2001 2002 2003 2004 2005

Polyurethane raw materials and
systems from Bayer:
Driving ahead in automotive
engineering
Changing demands made on the car and increased
responsibility towards the consumer and the environment
represent great challenges for the automotive
sector in terms of:
� Safety
� Environmental compatibility
� Low-cost manufacturing
� Model differentiation
� Comfort
4 5
Active and passive vehicle safety
The use of polyurethanes reduces the risk of accidents:
� Less driver fatigue
Comfortable seat cushions made of Bayfit ® HC and
HR, sound insulation with foam-backed carpeting
made of Bayfit ® SA.
� Improvement of critical crash
areas in the vehicle interior
Padded steering wheels made of
Bayflex ® 20/30, head restraints made of
Bayfit ® , crash pads made of Bayfill ® EA in
instrument panels and doors.
� Flexible body panelling to prevent
minor damage
Bumper covers, rocker panels, wings and side
panels in Bayflex ® ; energy-absorbing foam
made of Bayfill ® EA in bumpers.
Environmental compatibility
The entire life cycle of the components must be taken
into account when assessing their environmental
compatibility. Polyurethanes help to improve this
aspect through:
� Continuous weight reduction of components and
assemblies. Lightweight design conserves raw
material resources and reduces fuel consumption
and emissions.
� Long service life of polyurethane components.
� Recycling of used parts via material recycling or
via incineration with energy recovery, always
taking into account ecological and economic factors.

Low-cost vehicle manufacturing
Manufacturing costs include all steps up to
the final assembly of the component units in
the vehicle. Polyurethane helps to integrate
components, combine manufacturing steps
and simplify vehicle design work, e.g.
� Dual hardness seat cushions with anchoring
elements produced in one manufacturing
step
� Foam-backed carpeting
� Padded instrument panels
� Bumpers: ready-to-install energy-absorbing
foam mouldings complete with cover
and mountings
� Ready-to-install self-supporting headliners
� Helper springs made of Vulkollan ®
Polyurethane either as a foam or as a highstrength
composite material reinforced with
glass fibres, for example, offers enormous
advantages for lightweight construction and
parts consolidation.
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Car model differentiation
While car manufacturers strive for a limited
number of car types on the one hand, they
also want to increase the attractiveness of
their ranges by offering a wide variety of
models on the other.
Polyurethane components, in particular, enable
large model series to be differentiated,
and small series to be realised at a reasonable
expense.
Face-lifts for model updates and special
series are effective marketing instruments
and can be realised quickly and inexpensively
with polyurethane mouldings.
Comfort for the occupants
Polyurethane components in the form of
padding, attractively designed components
which are soft to the touch and sound insulation
all substantially improve vehicle comfort.
This is why a large volume of polyurethane
is used in mid-sized and top-of-therange
cars. Compact and sub-compact cars
are following this trend.
Polyurethane systems from Bayer
Applications
Seats, backrests
Headrests
Two-wheel vehicle saddles
Steering wheels
Instrument panels, trim
Seat and backrest shells, engine shrouds
Spare-wheel covers, roof elements
Headliners
Sun visors
Sound absorption elements, e.g. foam-backed carpeting
Energy-absorbing padding
Foam filling of cavities
Front and rear bumpers
Rocker panels, side mouldings, panels, wings
Modular window encapsulation
Spoilers, wind deflectors
Elastic components
Helper springs
Gaskets, filters
Range of properties
Flexible
Semi-rigid
Rigid
Elastic
Foamed
Microcellular
Integral skin foam
Solid
Fibre reinforcement or mineral filling
Our platform:
� High product quality
� Expertise in materials
� Process engineering
know-how
Bayfit ® HR/HC
Our advantages:
� Nearness to the customer
� Individually tailored concepts
� Service
7
Bayfit ® SA
Slab foam
Rebonded foam
Bayfill ®
Bayfill ® EA
Bayflex ® integral skin foam
Bayflex ® RIM/RRIM
Baydur ®
Baydur ® STR/Baypreg ®
Baynat ®
Urepan ®
Baytec ®
Vulkollan ®
� Innovative research and
development work
� Cooperation with experts from the
automotive and automotive supply
industries

Bayfit ® : comfortable
and safe
seats
Great demands are
placed on good car
seats. Criteria such as
climatic comfort and
driving safety are
decisive, in addition
to ergonomic
seat design, good
vibration damping and
long-term performance characteristics.
These demands are
ideally met by seat and backrest
cushions made of Bayfit ® .
Properties of various Bayfit ® foams
Density
DIN 53420 (kg/m3) Compressive strength 40%
DIN 53577 (kPa)
Compression set 50%, 70 °C, 22 h
DIN 53572 (%)
Elongation at break
DIN 53571 (%)
Tensile strength
DIN 53571 (kPa)
Tear resistance
ASTM-D 3574-91 (N/m)
8 9
This flexible polyurethane moulded foam is:
� High load bearing and permanently elastic
� Capable of being manufactured in virtually any shape
� Easy to manufacture in series production (inserts
for mounting the upholstery can be directly
moulded in)
� Capable of being manufactured with increased
lateral stability (dual-hardness technology)
Depending on the production process, a distinction is
made between the hot-curing moulded foam Bayfit ® HC
and the cold-curing moulded foams Bayfit ® HR-T
(based on TDI) and HR-M (based on MDI).
HC HR-T HR-M
30–40 38–48 45–60
3–7 2–8 4–12
2–4 4–8 4–8
120 – 160 100 – 150 90 – 140
80 – 140 130 – 200 100 – 160
200 – 400 200 – 450 160 – 250

10 11
Bayfit ® SA: custom-tailored
sound insulation
The acoustic properties of motor vehicles are taking
on increasing importance. In response to more stringent
noise legislation and growing demands for comfort
from motorists, both top-of-the-range models and
smaller, compact cars are being fitted with sound
absorption in the engine compartment and passenger
saloon.
Noise reduction techniques include:
� Foam-backed carpeting
� Bulkhead cladding
� Sound deadening engine shrouds
The Bayfit ® SA range of systems provides the perfect
answer to these and other requirements. In the case of
both air-borne and solid-borne noise, Bayfit ® SA
foams satisfy the most demanding acoustic requirements.
At the same time they provide the necessary
long-term performance properties and resistance to
high mechanical loads and climatic extremes.
Bayfit ® SA is available in grades ranging from high
resilient through standard and viscoelastic to
adhesive.
Properties of various Bayfit ® SA foams
HR Standard Visco- Adhesive
elastic
Density
DIN 53420 (kg/m
45 – 65 50–70 50 – 70 60 – 80
3)
Compression hardness 40%
4–7
DIN 53577 (kPa)
5–15 3 – 10 3 – 10
Compression set 50%
DIN 53572 (%)
5 – 15 5 – 15 7 – 15 10 – 20
Loss factor �
< 0,2 0,2 – 0,3
Oscillation-damping method
0,3 – 0,5 > 0,5

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Baynat ® : accurately fitting,
self-supporting, ready-toinstall
lightweight
headliners
Baynat ® is a specialised rigid foam
in sheet form which is compression
moulded into sandwiched headliners
in combination with fibrous facings
and decorative materials.
Baynat headliners are:
� Lightweight
� Self-supporting, even under the effects of heat
� Dimensionally stable
� Noise-absorbing
� Buckle- and rupture-resistant during installation.
Baynat ® slab foam
Baynat ® DTB* panels
Slab foam DTB * panels
Applications for simple for complex for semi-complex and
shapes shapes complex shapes
Density
DIN 53420 (kg/m
20–25 30–35 39–43
3 )
Compressive strength
0,09 – 0,14 0,13 – 0,20 0,15** N/mm2 DIN 53421 (MPa)
Flexural strength
0,12 – 0,18 0,26 – 0,35 1,95* N/mm2 DIN 53423 (MPa)
Strain in outer fibres
DIN 53423 (%)
19–26 23–24 —
Sheet thickness
with facings (mm)
— — 6,0*
* Measured on sandwich panels at 10 % deformation
** Sandwich panels produced on a continuous laminator
13

Baydur ® STR: lightweight
mouldings for interior and
exterior applications
Baydur ® STR is a tough, rigid polyurethane in foamed
or solid form which is produced in moulds in combination
with milled fibres or fibre mats. Various reinforcing
materials can be combined to form composites,
and anchoring elements, hinges and even pressure-sensitive
decorative facings can be integrated in a
single operation. This gives a wide range of application
options and has major advantages for economical
production through the integration of structural elements
and the reduction of manufacturing steps.
The mouldings offer:
� Very good mechanical strength with low weight
� Dimensional stability
� Low water absorption.
14 15
Baydur ® STR
Applications Trim panels Instrument
panel supports
Density
DIN 53420 (kg/m3 )
Typical applications include:
� Instrument panel supports
� Consoles and door panels
� Roof panels and seat trim
� Spoilers
� Seat shells and backrests
� Spare-wheel wells and covers
� Luggage compartment floors
� Engine shrouds
500 1.000
Weight per unit area of glass mat 300 600
(g/m 2 )
Specimen thickness
(mm)
Flexural modulus
DIN 53423 (MPa)
Flexural strength
DIN 53423 (MPa)
Impact resistance
DIN 53453 (kJ/m2 )
Elongation at break
DIN 53455 (%)
Heat deflection temperature,
B test, DIN 53461 (˚C)
4 3
1.100 3.600
30 95
18 40
2,1 2,2
140 200

Baypreg ® F: in good shape
Baypreg ® F is a special 2-component polyurethane
material for the production of fibre-reinforced automotive
interior fittings by compression moulding.
Baypreg ® F can be combined with natural fibres like
flax and sisal to produce thin-section trim panelling
with a low unit area weight.
Sandwich structures consisting of Baypreg ® F with
paper honeycombs or glass fibre mats are used to
manufacture sliding roofs and inlay mats for car
boots.
Mouldings made from Baypreg ® F in combination
with other materials feature:
� Very good mechanical properties coupled with
light weight
� Very good dimensional stability
� A low coefficient of linear expansion
� When the product reaches the end of its service
life, parts reinforced with natural fibres can be
thermally recycled, with all the CO2 bound in the
vegetable fibres being returned to the environment.
16 17
Baypreg ® F
Typical Door trim Inlay
applications supports mats
Density
DIN 53420 (kg/m3 )
— —
Fibre mat Flax/sisal 50:50 Glass mat
Paper honeycomb — 5/5
Weight per unit area
of mat (g/m2 )
Weight per unit area
of part (g/m2 )
Polyurethane content
of final product (%)
900 450
1.400 3.600
45 50
Specimen thickness (mm) 1,8 10
Flexural modulus
DIN 53423 (MPa)
Flexural strength
DIN 53423 (MPa)
Impact resistance
DIN 53453 (kJ/m2 )
3.500 3.500
20 30
15 15
Moisture content (%) 2,5 —
Coefficient of linear expansion

18
Bayfill ® : comfort and safety in
the interior
Padded instrument panels and interior trim add to the
comfort and safety of the occupants.
The components are pleasant to the touch, make for a
cosy atmosphere and contribute to reducing noise.
Driver tension is eased, making driving safer.
Coupled with cost effectiveness for users in the
automotive industry, these are key aspects of Bayfill ®
semi-rigid polyurethane filling foam.
19
Mechanical properties of Bayfill ®
systems
Bayfill ® –System
Density
DIN 53420 (kg/m3 )
Tensile strength
DIN 53571 (kPa)
Elongation at break
DIN 53571 (%)
Compression hardness at 40%
DIN 53577 (kPa)
Fogging
DIN 75201 B (mg)
Manufacturing process
High Low
density density
200-230 150-170
300 300
40 40
75 75
1,0 0,2
Parts are manufactured by inserting a
xxpreformed decorative material and
a support into a mould and foammoulding
a firm, durable
composite structure with
Bayfill ® as the lightweight
padding material. The process
also allows economical production of
complex contours.

20 21
Bayfill ® EA in safety components
for impact absorption
Energy-absorbing elements such as knee, pelvis and
head bolsters, which undergo permanent deformation,
are used in vehicle interiors to protect the occupants
in the event of a collision.
On the exterior, bumpers are provided with an energy-absorbing,
reversibly deformable foam core.
Designing integrated protection for pedestrians into
the front of the vehicle is also simpler using
Bayfill ®
EA foam.
Bayfill ® EA
Applications Bumpers Pelvic Thoracic Head
bolsters bolsters bolsters
Density
DIN 53420 (kg/m3 )
55–80 45–80 45–60 80–150
Compression hardness 40% 125 – 330200 – 700 70 – 150 700 – 2000
DIN 53577 (kPa)
Compression set 50 °C, 22 h

Bayflex ® RIM
for exterior body parts
Bayflex ® RIM is a moulded micro-cellular or solid
polyurethane material usually reinforced with fillers.
It is used for painted body parts, such as:
� Bumper covers � Spoilers
� Side panels � Wings
� Rocker panels � Door panels
22 23
The material permits complex shapes with long flow
paths. New component designs provide for wall
thicknesses of 1.5 to 2.5 mm. Bayflex ® RIM stands
out from other plastics due to its special combination
of properties:
� Light weight
� Rigid but elastic
� Impact resistance at low temperatures
� Low coefficient of thermal expansion
� Dimensional stability at relatively high coating
temperatures
Bayflex ® for modular window
encapsulation
Paintable or light-resistant Bayflex ® is used to encapsulate
windows and sun roofs. Due to its excellent flowablility
and low processing pressures as compared
with injection moulding, the material is particularly
suitable for large, curved windows.
Bayflex
Modular window encapsulation
Applications Valance
panels
Rocker panels
side mouldings
wings
weather
stabilised
formulation
weather
stabilised by
in-mould coating
® 180 Bayflex ® 190 Bayflex ® Bayflex ®
WR 40-6 MP 10.000
Wings
on line paintable
to 190 ∞C
Wollastonite
in the elastomer (%)
KMilled fibre MF 7980
in the elastomer (%)
— — 20–25 — —
17 24 — — —
Density DIN 53420 (g/m 3 ) 1,20 1,25 1,25 – 1,30 1,00 1,00
Shore A hardness DIN 53505 — — — 85 A 36 D
Tensile strength
DIN 53504 (MPa)
Elongation at break
DIN 53504 (%)
Flexural modulus
DIN 53457 (MPa)
Sag 1 h/ 160 ∞C/100 mm
overhang (mm)
Low temperature impact strength
Dynstat (-30 ∞C) DIN 53435 (kJ/m2 Tear propagation strength
DIN 53515 (kN/m)
)
25 25 25 15 18
>130 >80 30 – 50 >230 >280
— — — 22 33
1.200 1.600 1.700 – 2.000 — —
4 2 1 — —
>20 >15 ≥10 — —
Coefficient of linear thermal
expansion II
DIN 53752 (10
55 – 65 40 – 50 ≥33 — —
-6 m/m K)
Recommended moulded
wall thickness (mm)
≥2,2 * ≥1,8 ≥2,5 — —
* ( 1.5 mm, back-filled with EA foam in direction of fibres

Steering wheels made of
Bayflex ® 20/30 integral skin
foam
Integral skin foam articles with a wear-resistant,
compacted or solid outer skin and a
soft, flexible, cellular core are moulded
in one step. HCFCs, pentane or CO2
have now replaced CFCs as blowing
agents.
Overall density of test sheets
(kg/m3 )
Cellular core
Density
DIN 53420 (kg/m3 )
Tensile strength
DIN 53571 (kPa)
Elongation at break
DIN 53571 (%)
Compression hardness 40%
DIN 53577 (kPa)
Compression set 50 %, 70 °C, 22 h
DIN 53572 (%)
Skin zone
Tensile strength
DIN 53571 (kPa)
Elongation at break
DIN 53571 (%)
Tear propagation strength
DIN 53575 (kN/m)
24 25
Attractive, grained surfaces can be produced in accurate
detail. The articles can be coated for protection
against weathering and wear, or to lend colour.
Steering wheels all over the world are predominantly
manufactured using integral skin polyurethane foam.
If water is used as the blowing agent, the articles
must be painted.
Other applications include:
� Two-wheel vehicle saddles � Gear lever knobs
� Grab handles � Spoilers
� Protective mouldings � Head restraints
� Armrests
Bayflex ® 20/30
Type A Type B
Blowing agent R 134a CO2
400 400
380 – 400 380 – 400
1.100 – 1.400 1.200 – 1.600
80 – 120 70 – 110
300 – 360 330 – 400

26 27
Vulkollan ® polyurethane elastomers:
flexibility for innovative
design ideas
New materials often provide a springboard for innovative
designs. A good example of this is Vulkollan
from Bayer, which opens the door to innovative
designs in the chassis and the steering system.
Manufacturing method:
� Casting
Polyurethane elastomers based on Desmodur ® 15
and polyester have the following characteristics:
� Resistance to oil and grease
� Wear resistance
� Elasticity
� Flexibility over a wide temperature range
� Ease of assembly
� Freedom from maintenance
� Lightweight and space-saving
� Resistance to dynamic loads
� Scope for innovative design
Polyurethane elastomers have proved to be particularly
effective in:
� Damping and spring elements
� Gaskets
� Step bearings
� Bearing bushings
Progressive helper springs made of cellular
Vulkollan ® are widely used today in modern suspension
strut designs.

Recycling and
reuse
All polyurethane materials can be reused, either
by mechanical or chemical recycling or by thermal
treatment with recovery of the energy content.
The main processes are:
� Comminution of large quantities of foam remnants
into foam flocks which are then processed into
rebonded foam articles, e. g. carpet backings,
sound insulators, insulating mats.
� Polyurethanes can be finely ground and added to
one of the raw material components as a filler. This
also makes recycling in the original application
possible, e. g. in moulded foam for seat cushions
and - in the case of RIM technology - in body
parts.
� Comminuted and ground polyurethanes are mixed
with polyurethane binders and compression moulded
or cast in moulds, for example, rear-window
shelves or workbench tops.
28 29
� Another recycling technique is glycolysis - the
liquefaction of polyurethanes with glycols. The
resultant recyclate polyols are mainly processed
into rigid foam and structural
components reinforced with
glass fibre mats (Baydur ®
STR).
� The techniques
of pyrolysis,hydrogenation
and
synthesis gas
production yield raw
materials for the petrochemical
industry.
� Polyurethane waste can be used as a reducing
agent in the smelting of iron ore.
� Incineration with energy recovery. The exhaust gas
emissions from the thermal recycling of polyurethanes
in modern plants have been shown to be safe
and within the statutory tolerance limits.
Ecological and economic factors determine the choice
of material recycling process or incineration with
energy recovery. The method and scope of disassembly
of the plastic components must be geared to the
recycling processes used and the available marketing
options.
Even if mechanical and chemical recycling (e.g. glycolysis)
are used extensively, it will still be necessary
to dispose of some of the plastics at the end of their
useful life. Ultimately, petrochemical feedstock
recovery or incineration with recovery of the energy
content are the only methods capable of easing the
burden on available landfill space.

Lending a helping hand
The future of automotive engineering lies in individual
design solutions which ensure maximum cost
effectiveness.
30
The versatility of high-quality polyurethane raw materials
and systems from Bayer, our experience in polyurethane
chemistry and Bayer's broad range of services
and global resources provide our customers and processors
with the tools they need to master this challenge.
Are you a designer, design engineer or someone involved with
the problems of the automotive and automotive supply industry?
We can help you. Just get in touch with us - anywhere in the world!
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