3D Printing / Additive Manufacturing (AM)
Additive manufacturing (3D Printing) is an effective way to rapid-prototype high quality parts, create molds for investment casting or even produce finished goods. The properties of starting materials like polymers must be optimised to ensure 3D printed parts will perform as intended. To ensure that lab scale properties are accurate, all materials must be dispersed homogeneously in the sample, and bubbles / voids must be removed before testing. The same is true at the manufacturing scale.
Adhesives/ Sealants
Adhesive and sealant products must be mixed homogeneously and free of unwanted bubbles & voids to deliver the best performance. Optimisation may require dissolving and dispersing tackifiers into pressure sensitive adhesives, blending polymers with filler and vacuum degassing moisture cured urethanes & silicone products, dispersing rheology modifiers like fumed silica, incorporating structures like hollow glass micro balloons to reduce density etc.
Aerospace and Defense
Epoxies are frequently used as adhesives, gap fillers & liquid shims, potting compounds for electronics, impregnated and pre-impregnated (pre-preg) fibers, and even coatings. They can be formulated with a low viscosity for application like conformal coatings or with higher viscosity and even thixotropic properties when they need to stay in place and not “slump” for applications like abradable materials. Epoxies can be packaged into cartridges or syringes and extruded to simplify handling and application. Their reaction/cure can also often be accelerated with heat to further reduce process times.
Cannabis
As the cannabis industry continues to grow, manufacturers are looking for ways to process products more efficiently and at higher volumes with greater differentiation. Optimised extraction process, efficient solvent stripping methods and fast mixing / blending processes are some of the best ways to reduce cost and increase throughput. Although ethanol is rapidly removed from distillate, butane extracted distillate can require several hours (or even days) in vacuum ovens to reduce the butane content to safe levels. An optimised vacuum mixing method has been proven to reduce the time required for butane purging/stripping processes to a few minutes.
Cosmetics
Mixing & dispersion during the formulation and manufacturing processes is key to the performance of formulations. Pigments and performance enhancing additives such as emulsifiers, moisturisers, film formers, waxes & oils, etc. must be properly dispersed to provide the desired effect. A powerful mixer that can provide variable amounts of shear, depending on the product requirements, is important. Mixing in single-use containers is convenient and helps avoid cleaning when formulating the many iterations that are often necessary to optimise a product.
Ceramics
Ceramic products often start as a combination of powders, binder, and a solvent such as water or alcohol. The powders often vary in size and shape (morphology) so that they will pack together efficiently to provide the desired density, porosity, and mechanical properties. It is important that any agglomerates in these powders are broken down and homogeneously dispersed so that the finished product is not weakened by areas of unmixed material. For slurries bubbles and voids should also removed to prevent negative effects on mechanical, thermal, electrical properties. Once materials have been properly mixed and deaired it can then be formed into the desired shape by injection molding, dry pressing, casting, 3D printing, etc. and then baked / sintered into a solid body.
Compounding pharma
Product customisation, coupled with patients’ urgent needs for treatment, necessitate almost constant mixing, milling/dispersing, and blending. Compounding equipment must work fast to keep up with need. It is also critical that the equipment provides perfectly homogeneous mixing / milling / dispersion of a broad range of materials to guarantee accurate and precise dosage of Active Pharmaceutical Ingredients (APIs) can be achieved. It must also be easy to clean thoroughly and/or process materials in single-use containers so cross contamination is avoided.
Paints and inks
High shear milling and dispersion equipment may be necessary to reduce the particle size of pigments or additives to achieve the desired fineness of grind, surface finish, and/or color. High powerful, high-speed mixing is often used to accelerate R&D or manufacturing. Equipment should be able to be cleaned easily or work with single use mixing vessels & components. This saves time, reduces the use of cleaning solvents, and minimises the potential for erroneous test results cause by cross contamination.
Polyurethanes
Fast reacting urethanes & polyurethanes can be challenging to mix and test at a lab scale as they may start to cure or blow (foam) seconds after combining components. Extremely rapid mixing is needed to thoroughly mix and still have time to pour & cast test parts. Mixing with single use mixing vessels & components is also highly recommended as the materials are likely to cure before they can be cleaned off. For materials other than foams, it is often necessary to deair and/or vacuum degas materials prior to curing to prevent voids and achieve the best physical properties.
Silicone
Silicones are often mixed with pigments for aesthetic or functional purposes (e.g., barium sulfate for radiological opacity), with additives such as rheology modifiers and adhesion promoters, or even with active pharmaceutical ingredients for drug delivery. They must be mixed thoroughly, at the right ratio, and without voids to achieve the best possible physical properties. Controlling temperature during the mixing process will help to maximise working time. Vacuum mixing is also helpful in many cases to remove difficult voids as well as entrapped air and gasses. It is one of the best ways to avoid bubbles which can be formed by expanding gasses during a heat accelerated cure.
Light emitting diodes (LED)
The key to achieving a long lasting and rugged product with any type of electronics is to encapsulate / “pot” the components. This hermetically seals them to keep out moisture & other materials that could damage the product or reduce performance. Potting also protects delicate components from vibration and shock. Properly mixing the potting compound ensures that it will cure fully and achieve the best physical properties. Vacuum degassing the potting compound will prevent bubbles or voids (especially when using heat to accelerate cure). It is an important step as those bubbles & voids could potentially cause a failure if unaddressed.
Batteries
With the ever-increasing demand for high performance lithium-ion batteries used in Electric Vehicles (EVs), solar power storage, consumer electronics the testing and quality control of materials during the battery manufacturing process critical. A key component is the battery slurry, a complex suspension made by mixing an active material like graphite with a binder powder, solvents and additives. The slurry is applied to multiple layers if aluminum foil and copper film to create the battery cell. Slurry mixing is challenging as lithium-ion battery slurries are viscous, containing raw materials that must be precisely deagglomerated. The mixing process must also be highly repeatable to ensure optimal product performance.
Epoxies
Maximum performance can be achieved by using the correct ratio of resin to hardener, mixing thoroughly, and removing bubbles/voids from the material. Once the resin and hardener are combined they begin to react, so high speed mixing will maximise working time. A programmable system ensures that the process is repeatable and that consistent, high quality results can be achieved. Vacuum mixing is recommended for conductive or insulative systems, heat cured systems, or any materials that will be used in space-based applications.
Dental
The development of modern dental materials has allowed advancements in modern dental care. Higher solids content which leads to higher compressive strength requires more powerful mixing methods and better control of temperature. More advanced deairing methods are also necessary as bubbles and voids are more difficult to remove from these new systems. Furthermore, process time in R&D and production must be reduced to keep up in these competitive markets. The right mixer makes a big difference when trying to overcome new challenges.
Automotive
Iterative work to optimise materials for the automotive industry requires a lot of mixing. The mixer must be versatile enough to disperse pigment in paint, formulate SPUR sealants, or even vacuum degas high performance epoxy adhesives. A centrifugal mixer is the best choice for nearly any small-scale mixing requirement in the automotive industry. This is because they generate meaningful results quickly and do not delay the learning process with unnecessary clean-up.
