Premixed & Frozen materials can save time and money
Many two part adhesives, sealants, and potting compounds can be supplied premixed and frozen. The proper process consists of mixing the reactive compounds, degassing to eliminate entrapped air, package into pre-portioned syringes or cartridges, and freezing to suspend the reaction. When done properly all of the desirable properties of the compound are maintained. Proven processing methods, used by most manufacturers, allows control so that all products meet quality standards. This assures the ultimate finished product meets all the requirements.
Premixed and frozen product saves time and money, reduces waste, improves safety and increases productivity. This allows users to focus on manufacturing and eliminate the need to spend valuable time processing adhesives which can be messy, difficult and inconsistent.
Premixed and frozen systems will greatly reduce waste. Precise mixing and packaging allows users to simply remove syringes from the freezer, let them thaw, and use immediately. There is no more time wasted on mixing a large batch only to use a portion of it and discard the rest. Trying to get every drop out of a bucket or bottle is next to impossible when the end user does the weighing and mixing. Dispensing a syringe or cartridge of adhesives guarantees that more material can be used in the production line.
Overall cost actually goes down when using premixed and frozen material as reduced material handling, decreased process time and faster turnaround time more than offset the slightly higher price of frozen products.
Delivering a Quality Product
Frozen products guarantee that the two component product is weighed and mixed properly. Manufacturers will test for important factors including work life, bond strength, viscosity, density, and hardness. This allows for frozen material to be guaranteed to meet both the material manufacturer’s internal QC requirements and customer’s individual specifications
There are several techniques for handling the premixed and frozen process. The best is batch manufacturing which allows important aspects of the system to be tightly controlled. Limiting lots (generally 100 per lot but can vary based on the product) also ensures that working time is not depleted during production.
Rejected parts can occur due to improper weighing and/or mixing of the adhesive or encapsulant. Experienced processors of premixed and frozen material can guarantee that the resin to hardener mix ratio is always accurate and homogeneously mixed. Eliminating air entrapment is also a contributing factor in the efficacy of any polymer. It reduces the risk of cracking and/or delamination. Premixed and frozen polymers are not only properly weighed and mixed but also degassed to greatly reduce entrapped air.
Many epoxy, silicone, urethane, and polysulfide products can cause adverse reactions when exposed to the skin or via inhalation. In the premixed and frozen configuration, the handler has a significantly lower possibility of chemical exposure. This results in a greatly reduced potential for contact dermatitis or other exposure hazards.
Frozen products are kept frozen during shipment with dry ice and specially insulated boxes. Material is sent via next day shipment (or international priority) and must be stored in a commercial freezer at -40ºC (or below) upon receipt. To ensure complete function of the adhesive and to maximize the shelf life, frozen syringes should not be exposed to higher temperatures unless it is being thawed and ready to use immediately.
When considering all the parameters for handling two part materials, premixed and frozen is a valuable method to reduce problems associated with mixing, weighing and chemical exposure. Long term costs are reduced as reliability is greatly enhanced. Premixed and frozen also greatly reduces risk of operating error and it being applied to a critical component.