Glue ideas for polycarbonate
Polycarbonate plastic & glue for polycarbonate plastic’s have evolved hand in hand. First discovered in 1898, polycarbonate remained a chemical oddity until mid 1953 when Dr Hermann Schnell, a young German chemist working in Bayer, patented Makrolon®, the worlds first polycarbonate plastic. In 1960, the US giant General Electric began manufacturing their own polycarbonate called Lexan®. The rest is history!
Polycarbonate is a highly durable industrial plastic, with exceptional transparency to visible light. Unlike most other plastic’s, polycarbonate is capable of undergoing large hot moulding deformations without cracking or breaking. This makes it an excellent plastic for prototyping applications where transparent or electrically non-conductive parts are needed, which cannot otherwise be made from sheet metal. Polycarbonate has thousands of applications, from CD manufacture to aircraft cockpit canopies, but the largest user of polycarbonate is the construction sector, where is a replacement for glass.
Luckily, polycarbonate is a relatively easy plastic to stick. Either to itself or to other materials, there are glues available for most applications. Typically, polycarbonate does not need any type of cleaning, however, depending on the application, we often suggest degreasing with X320 degreaser. For cross bonding polycarbonate to other materials such as metals (in particular ferrous metals) surface cleanliness is important!
The choice of adhesive depends very much on the application. Typically, adhesives or sealants for use on polycarbonate must be clear, in order to maintain optical clarity.
For bonding small polycarbonate parts, cyanoacrylate glue (aka Super-Glue) is an option. Superglue does have its limitations however. It is not suitable for use in applications which require impact strength or applications where water exposure is inevitable. Superglue is not suitable if the gap between the materials being glued is in excess of approximately 0.5 mm & excess application of superglue may lead to stress cracking on the polycarbonate. Only suggested for small gluing applications.
Two-component epoxy resins, while having excellent adhesion & strength, are liable to turn yellow upon exposure to UV light. Stress cracking while the adhesive is curing, is also a possibility.
Single component acrylic cements, such as Scigrip 16 (medium thickness syrup ) & Scigrip 4SC (water thin liquid ) are excellent choices for many applications. The choice of which one to use depends on the application. Scigrip 16 is typically used in applications where fast cure with gap filling is required. Scigrip 4SC is the ideal candidate for gluing polycarbonate, flat on flat. Both adhesives are commonly used for the manufacture of polycarbonate housings, signs, letters and display units.
Two-component polyurethane (PU) is the choice glue for gluing small units or prototype parts. Scigrip SG55 PU is certainly recommended for its ease of use, clarity and bond overall strength. It boasts strong resistance to UV light, combined with excellent impact strength.
Two-component acrylic glues are by far the best choice for gluing polycarbonate in structural applications. Depending on the exact application, and the service conditions for the bonded parts, there is a two-component acrylic adhesive to suit most applications.
Scigrip 42 is a water clear two component acrylic glue with exceptional strength and ease of use. Developed for use in many polycarbonate applications such as sign manufacture and repair, and other plastic fabrication processes such as display case manufacture. Scigrip 42 is also quite suitable for cross bonding polycarbonate with other plastics such as acrylic, polyester and butyrate.
For applications where ultimate structural strength and environmental resistance is the prerequisite, Scigrip offer a range of premium quality structural adhesives based on their novel patented chemistry.
SG5000 is one such product. Available in a range of handy cure times, SG5000 is suitable for bonding polycarbonate to itself, and cross bonding polycarbonate with metals such as aluminium and stainless/mild steel. No surface abrasion is required at all!
SG300 & SG800 are also quite suitable. Again, the choice is application dependent but the Scigrip products are unique in that they offer users primerless application.
For sealing polycarbonate joints, the premium product to use is our U69 sealant. U69 is a water clear, high quality, durable & elastic sealant. U69 is the choice product for sealing joints in exterior illuminated signs, which are fabricated from polycarbonate. U69 will very effectively exclude the ingress of water, thus preventing electrical faults.
For all polycarbonate bonding applications, from prototype manufacturing to large scale structural bonding within the construction sector, we have a glue solution for you. Our chemical & mechanical test laboratories, and those of our partner, Scigrip, are available to you!
Please contact our sales office or laboratories for specific advice in all aspects of gluing or sealing polycarbonate!