PLEASE READ ABOUT TOOLING SOLUTIONS IN THE NEXT CHAPTER.
THERMOSET POLYESTER RESINS, HARDENERS, ADDITIVES
THERMOSET RESINS, HARDENERS AND CURING ADDITIVES
Unsaturated polyester resins
Unsaturated polyester resins are thermosetting resins created when glycols combine with saturated or unsaturated dicarboxylic acids to form polyester. The final resin is produced by dissolving the resultant solid polymer (at room temperature) in a solvent, typically styrene, which is unsaturated and reactive.
By adding organic peroxide, an initiator in the crosslinking reaction, a complex three-dimensional network is formed, resulting in a solid, irreversible state.
To produce polyester resins, Bang & Bonsomer, together with Polynt, manufactures various anhydrides (such as phthalic and maleic anhydride) and dicarboxylic acids (such as fumaric acid). Using these raw materials and the solid formulation expertise accumulated over the years, we have developed the following families of resins.
Learn about the products: polynt.com
Vinylester Resins
Epoxy resin and an unsaturated monocarboxylic acid react to create vinyl ester resins. A reactive monomer, such as styrene, is used to dissolve the resulting polymer, creating a solution that can be used and cured like normal polyester resins.
Due to their advantageous combination of excellent mechanical properties, high thermal deflection temperature, and resistance to corrosion from a wide range of chemicals, Polynt vinyl ester resins are used in high-performance composites.
These resins can be produced for infusion, lamination, and filament winding, and are available either unpromoted or promoted.
For more information: polynt.com
Gelcoats and Topcoats
A flexible and durable main layer used in the creation of composite parts is called a gel coat.
Most gel coats are applied as in-mold coatings, which is the first step in the creation of composite parts.
Throughout the remaining stages of manufacturing, in-mold gel coats protect the mold from abrasion and chemical attack while providing a releaseable covering to facilitate de-molding operations.
For composite parts, gel coats often serve as the outer coating, giving the part both color and texture.
They can have a variety of appearances, from transparent tints that allow you to see through to pigmented coats that can be combined with an infinite number of colors.
Moreover, they protect the components from corrosive chemicals, moisture, and environmental elements.
For more information: polynt.com
SMC, BMC compounds
SMC and BMC are thermoset composite materials primarily composed of unsaturated polyester resins, mineral fillers, reinforcing fibers, and additives.
BMC and SMC can be moulded using hot plate technologies such as compression moulding, injection, and transfer.
During molding, a crosslinking reaction occurs due to the temperature and pressure, and the material takes the shape defined by the mould’s geometry. Demolding and deburring are the final stages of the process.
The expertise and experience of Polynt laboratories enable us to customize products to meet specific customer needs.
SMC (Sheet Moulding Compunds)
SMC are composite materials reinforced with glass or carbon fibers, with lengths ranging from 12mm to 50mm. They are produced as sheets with a width of 1300mm and a thickness of 2-3mm. SMC are particularly suitable for compression moulding of flat, medium to large-sized geometries.
The product can be packaged in rolls or boxes according to the customer’s specifications.
BMC (Bulk Moulding Compounds)
BMC are composite materials reinforced with glass or carbon fibers, with lengths ranging from 3mm to 24mm. They are produced as homogeneous bulk. BMC are particularly suitable for compression moulding, injection, and transfer molding. The product is packaged in 10-20 kg bags according to the customer’s requirements.
Compared to more common thermoplastic polymers, thermosetting compounds offer superior technical characteristics and performance, such as, but not limited to:
- High mechanical properties in terms of rigidity and impact resistance;
- Dimensional stability at high temperatures, due to the intrinsic nature of thermoset materials;
- Fire resistance, with halogen-free, filled materials;
- Chemical and weathering resistance, especially formulated for outdoor applications;
- High-quality surface “CLASS A” finish for the automotive and transport industries.
Eco-friendly solution
Parts made with traditional materials, such as steel, aluminium, and concrete, have a high environmental impact in terms of energy consumption, raw materials, and carbon dioxide emissions. For these reasons, SMC and BMC provide the best solutions to today’s needs:
- Weight reduction of the component, leading to a significant decrease in fuel consumption and CO2 emissions;
- Reduced processing steps, such as drilling and welding;
- The thermosetting compounds are sustainable and recyclable through co-processing in cement kilns, in compliance with the European Waste Framework Directive (WFD) 2008/98/EC.
For more information: polynt.com
Fire-retardant Thermoset
Bang & Bonsomer works closely with one of the world’s leading chemical companies, Mäder Group, to offer fire-retardant thermoset coatings, resins, and gel coats.
Total EN 45545 Solutions for Flame retardant Composites: Gel- & Topcoats, Resins and Coatings
Mäder develops and produces coatings, resins, and gel coats in-house. This enables fast, customer-oriented developments that meet various requirements as systems.
More info: mader-group.com
R118 compliant flame retardant composite solutions: Gelcoats, Topcats and Resins
Mäder develops high-value-added products for the transport sector, particularly for buses. The solutions offered are characterised by ease of use and fire/smoke protection in accordance with the R118 standard. They can be used for many interior and exterior parts.
More info: mader-group.com
Peroxides
We work with Arkema to provide our clients with suitable peroxide solution.
For more information: luperox.arkema.com
Epoxy Resins and Hardeners
The family of basic elements or dried end products known as epoxy includes epoxy resins. The collection of reactive prepolymers and polymers known as epoxy resins, commonly referred to as polyepoxides, contains epoxide groups. Epoxy is another name for the functional group made up of epoxides. An oxirane is the term given to an epoxide group by IUPAC.
Epoxy resins can react (cross-link) with a variety of co-reactants, such as polyfunctional amines, acids (including acid anhydrides), phenols, alcohols, and thiols, as well as with themselves through catalytic homopolymerisation (usually called mercaptans). The cross-linking reaction is frequently referred to as curing, and these co-reactants are often referred to as hardeners or curatives.
A thermosetting polymer is created when polyepoxides react with one another or with polyfunctional hardeners. This polymer frequently has good mechanical properties and excellent thermal and chemical resistance. Metal coatings, electronics/electrical components/LEDs, high-tension electrical insulators, paint brush manufacture, fibre-reinforced plastic materials, and structural and other adhesives are just a few of the many uses for epoxy.
Bang & Bonsomer offers a wide portfolio of epoxy resins and hardeners, together with Entropy Resins, Pro Set, West Systems, and Elantas.
Read more about our products here:
Bio based Entropy: entropyresins.com
Marine epoxy Pro SET: prosetepoxy.com
DYI West System: westsystem.com
Industrial Epox: elantas.com
Additives for thermosets
Check out additives solutions with Lubrizol Corporation: lubrizol.com
Accelerators and Inhibitors
A substance that, when combined with a catalyst-catalysed resin, will accelerate the chemical reaction between the two, either in the polymerisation of resins or the vulcanisation of rubber, is also referred to as a “promoter.” Diethylaniline, cobalt naphthenate, and cobalt octoate are a few examples.
The cross-linking process that cures a thermoset resin is initiated and controlled by initiators, catalysts, and inhibitors.
With thermoset resins, initiators, also known as catalysts, are employed to initiate the curing (molecular cross-linking) process. In various room temperature curing moulding applications, methyl ethyl ketone peroxide (MEKP) and benzoyl peroxide (BPO) are used in different formulations. There are additional initiator formulations that are heat-activated or have specific curing properties.