Polyurethane is not all the same. Depending on the requirement - mechanical load capacity, insulation effect, surface quality or food compliance - a different system type is used. BKT Germany formulates all five system types from just 100 kg polyol, precisely matched to the customer profile. Here is an overview of when which system is the right choice.
Integral Foam Systems: Robust Skin, Soft Core
Integral foam systems produce moulded parts with a robust outer skin and a softer core. Moulded part densities range from 220 to 600 kg/m3, Shore hardness from 10 to 90 Shore A. Variants can be set to viscoelastic, antistatic or hydrophobic. Typical applications: ergonomic armrests, handles, seat cushions, operating table pads and safety padding. Through targeted control of skin formation, BKT achieves surfaces that are extremely durable and premium to the touch without additional coating.
Rigid Foam Systems: Maximum Insulation
Rigid foam systems offer densities from 35 to 120 kg/m3 (special packaging foams from 5 kg/m3) and excellent thermal insulation with lambda values from 22 mW/mK. Application areas include thermal transport containers, beer barrel encasements, window profiles and structural foam for bathtubs. BKT optimizes flow behaviour so that even complex cavities are filled gap-free and pressure-stable.
Flexible Foam Systems: Comfort and Acoustics
Flexible foam systems offer moulded part densities from 55 to 250 kg/m3 with individually adjustable compression hardness. Variants with barite or chalk filling are suitable for acoustic applications, heat-resistant up to 150 degrees C. Typical products are vehicle seats, office chairs, medical pads and sound-absorbing components. The systems are optimised for back-foaming of textiles and films.
Rigid Integral Foam Systems: Lightweight Meets Load Capacity
Rigid integral foam systems combine Shore hardness of 35 to 85 Shore D with densities from 220 to 900 kg/m3 and tensile strengths of 3 to 16 N/mm2. High rigidity at low weight, good paintability and laminatability, plus often self-releasing formulation for fast cycle times. Applications: housing parts, energy-saving windows, cold brackets and pipe supports.
Compact Systems: High Performance Under Extreme Conditions
Compact systems achieve densities from 1,000 kg/m3, a hardness spectrum from 10 Shore A to 85 Shore D and tensile strengths up to 60 N/mm2. Special features include FDA/food approval, UV stability, light fastness and extreme impact resistance. Application areas: electronic potting, concrete formwork, stair treads, filter potting and industrial protectors. BKT compact systems retain their mechanical properties even under UV radiation or chemical stress.
| System Type | Hardness Range | Key Advantage | Typical Application |
|---|---|---|---|
| Integral Foam | 10-90 Shore A | Robust outer skin | Handles, armrests, safety padding |
| Rigid Foam | Cellular structure | Lambda from 22 mW/mK | Thermal containers, window profiles, insulation |
| Flexible Foam | Variable | Acoustics & comfort | Seats, insoles, acoustic components |
| Rigid Integral | 35-85 Shore D | Rigidity & lightweight | Housings, window construction, pipe supports |
| Compact System | 10 Shore A - 85 Shore D | Impact-resistant & FDA-compliant | Electronic potting, moulded parts, seals |