They help eliminate the need for mechanical fasteners and are safe to use in many environments.
When choosing adhesives sealants, it’s important to consider the substrates you will be working with and the environmental conditions they must withstand. This will help ensure that your bond is strong and long-lasting.
Polyurethane
PU adhesives and sealants are very common in aerospace applications. They provide high-strength bonding and resistance to harsh conditions. These materials also have many other benefits, such as stress absorption and vibration dampening. They are also paintable and offer maximum UV resistance.
These adhesives are produced by reacting isocyanate monomers with polyols. They can be manufactured from a variety of starting materials and can vary in physical properties, such as viscosity and adhesion to different substrates.
Polyurethane adhesives are available in one- and two-part systems and can be applied either by hand or with a dispensing system. They cure through a chemical reaction with atmospheric moisture. They can be used to bond a wide range of materials, including FRP, SMC and other plastics. They are durable, low-flammable and do not contain ozone depleting chemicals.
Silicone
Silicone is a versatile adhesive that uses an elastomeric formula to create a durable bond. It can be used in many industrial applications due to its flexibility and heat resistance. It is also non-chemical, which emphasizes environmental safety.
Engineers carefully consider the thermal and environmental conditions a bond will be exposed to when selecting an adhesive. They may also require a specific surface appearance, acoustical or electrical properties, chemical stability, fire barriers, or UV resistance.
Silica is the most common ingredient in silicone, which is a naturally occurring mineral found in sand, soil, and granite. Itâs also used in a number of household maintenance and repair products. Its quick cure time is essential for aerospace applications to meet strict flight schedules. It can also help eliminate downtime for repair or assembly.
Acrylic
A must-have in every builderâs tool box, acrylic adhesives seal joints and cracks to prevent water damage that can cause warping of wood or mold spores to grow. They also protect constructions from weathering, providing durability to ensure longevity and eliminate restorative work in the future.
They achieve extraordinary adhesion without primers, saving installation time and cost. They are also environmentally friendly and fully compatible with building materials. This reduces the risks of debonding, degradation or reaction with surface surfaces and makes them a great option for bonding dissimilar substrates.
Structural acrylic adhesives are also used in aerospace applications to assemble, mount and repair aircraft and spacecraft parts. They provide high temperature limits and impact and vibration resistance and can bond a wide range of substrates. They are available in a variety of viscosities from liquid to paste.
Rubber
Rubber adhesives and sealants are used to bind glass, wood, paper, plastic, metal and leather. They offer low permeability, inherent tackiness and good aging resistance. They also offer chemical resistance. They are available in a variety of forms including caulk, latex emulsions, and solvent-based versions. Butyl rubber caulk is the most popular for its strong bonding power and long lifespan.
Aircraft structures are subject to harsh environmental conditions, so they require an adhesive that can withstand these extremes. It is important to select the correct type of adhesive for your project, and to follow the instructions carefully.
Speciality aerospace adhesives can be expensive to develop and produce, and they may require stringent quality control procedures. These factors may impede market expansion. Also, some types of adhesives can be volatile and require proper storage and handling.
Polyolefin
Polyolefins are a group of thermoplastic materials that are moldable when heated and harden to a rigid state after cooling. They are produced by the polymerization of ethylene and propylene, which can be sourced from fossil fuels or renewable resources.
Polyethylene and polypropylene are the most common types of polyolefins. They are used in many different applications, including packaging and automotive components. Polyolefin hot melt adhesives can be used to bind these materials, and they provide a strong bond that resists heat and chemicals.
A polyolefin adhesives sealant must be designed for a specific application to ensure proper aerospace pma performance and durability. Several factors affect the adhesion process, such as substrate preparation, ideal temperature and pressure, and contamination. These adhesives also need to have excellent thermal stability characteristics