Different types of material are used for
reinforcing of extruded profiles made of rubber and thermoplastic materials.
One such popular material is treated glass cords used extensively in the
building and the automotive industry. Some of the features of glass cords
that makes it suitable for extruded profiles include:
- Prevention of stretching
- Reduction of waste
- On line cutting permissible
- Good weathering properties
Characteristics of Glass Cords
In the manufacturing of glass Cords, glass fibres are treated with
formulations of special latex/resin. This treatment of special kind gives
certain kind of advantages. It prevents inter-filament abrasion and enhances
product life. Here a solid basis is provided for chemical bond between glass
fibres and a vast range of extruded rubber profiles as well as thermoplastic
elastomers. Glass Cords are plied and twisted into constructions of uniform
diameters. Smooth surfaces ensures easy introduction through dies into the
extruded profiles.
Glass Fibre displays excellent stress:strain properties as compared to many
other types of reinforcement media. The following graphs corroborates the
point.
New Methods of Reinforcing extruded Profiles
Further developments made in the processing technology is now allowing
profiles made of thermoplastic to be extruded with continuous fibres
throughout their length. And making this possible is an unique high
pressure, crosshead die. This permits the volume of glass and its position
within the profile to be perfectly engineered for meeting the specific
requirements of the design. The production process of manufacturing this
reinforced extruded profiles with continuous length of glass fibres is shown
here:

The profiles manufactured this way have been able to increase their
rigidity to a whopping 500% as compared to conventional thermoplastic
profiles. Two key factors in this process are the bond strength between
matrix and the fibre as well as the type of crosshead die used. Listed here
are some of the chief advantages:
- High strength-to-weight ratio
- Resistance to corrosion
- Electrically insulated
- Thermal insulation
- Dimensional stability under thermal loading
- Electromagnetic transparency
Reinforced Vs Non reinforced Profiles
The following table looks at some of the mechanical properties of
reinforced and non reinforced profiles in case of PVC material. The figures
that are reproduced here are taken from ideal situation in laboratory
conditions, before you decide to go for reinforced profiles it's better to
get expert advice.
| Property |
Non- reinforced Profiles |
Reinforced |
| Strain at Failure (%) |
12 |
16 |
| Modulus(MPa) |
600 |
1100 |
| Strain at yield(%) |
4 |
6 |
| Tensile stress at yield(MPa) |
32 |
82 |