If you are searching for silicone with superior application properties such as enhanced biocompatibility, high tensile strength, and long lifespan, then platinum-cured silicone is your premium silicone of choice.
In this article, you learn the unique properties of platinum-cured silicone, its manufacturing process, advantages, limitations, comparisons, and industry applications
But first, what exactly is platinum-cured silicone?
What is Platinum Cured Silicone?
Platinum-cured silicone, also known as addition cure silicone, is a superior type of silicone cured using platinum as a catalyst during its production process.
Standard Silicone and Platinum-Cured Silicone – Differences
Standard silicone and platinum-cured silicone are forms of silicone that you can use as gaskets, seals, or for other insulation requirements.
However, for the standard food grade silicone, the curing technique used is oxidation using peroxide.
Unfortunately, this leaves you with a rubber silicone that will not withstand high temperatures. It is also less resistant to chemicals.
For the platinum-cures silicone, your curing technique is enhanced to improve the silicone rubber’s strength, elongation, and resistance to both heat and chemicals.
To achieve this you need to use a small quantity of platinum as a catalyst.
So, for addition cure silicone, you get the best you can ever get from your silicone, but you have to spend more.
Platinum-Cured vs. Peroxide-Cured Silicone – Comparisons
Platinum-cured and peroxide-cured silicone are two of the major types of silicones you can choose from for a wide range of industry applications.
While the two share some similarities, they also have their major differences. The table below provides you with a clear comparison between these two types of silicones.
Table Comparing Addition Cure vs. Platinum-Cured Silicone
| Comparison Properties | Platinum Cured Silicone | Peroxide Cured Silicone |
| Similarities | ||
| Durable/Long-lasting | ☑️ | ☑️ |
| Resistant to high-temperature | ☑️ | ☑️ |
| Non-Toxic (Food-grade) Silicone | ☑️ | ☑️ |
| Water-proof | Outdoor Application | ☑️ | ☑️ |
| Microbial growth resistance | Suitability in medical environments | ☑️ | ☑️ |
| Different Hardness Levels/Grades | ☑️ | ☑️ |
| Suitability for Detailed Parts | ☑️ | ☑️ |
| Good Electrical Insulation | ☑️ | ☑️ |
| Processing Ease | ☑️ | ☑️ |
| Differences | ||
| Cost-effective | ☑️ | |
| Most Complex Manufacturing Processes | ☑️ | |
| Faster Curing Rate | ☑️ | |
| More Clarity and Consistency | ☑️ | |
| More Elongation and Tensile Strength, | ☑️ | |
| More Temperature Resistant | ☑️ | |
| Low Volatility | ☑️ | |
| More Resistance to Contamination | ☑️ | |
| More Chemical Resistant | ☑️ | |
| Longer Shelf-life | ☑️ | |
| Resistance to Shrinkage | ☑️ | |
| Low Odor and Taste | Mostly Used Medical applications + Most ideal food-grade silicone | ☑️ | |
| More Application Flexibility, Elasticity, and Resistance to Temperature and UV + Outdoor Application | ☑️ | |
| Most suitable for Less Demanding applications | ☑️ | |
| Enhanced pump life -peristaltic pump applications | ☑️ | |
Properties of Platinum-cured Silicone
Below are some of the properties that make additional cure silicone of popular use in different industries:
Long Lifespan and Does Not Shrink
Components made from additional cure silicones have long lifespans. This is mainly because they do not break down and are resistant to harsh environmental factors.
If you use additional cure silicone for your casting or masks, they can last up to 45 years with no shrinkage.
Stability In High-Temperature Conditions
Addition cure silicone will remain stable even at extreme temperatures of -73 degrees Celsius to 204 degrees Celcius ( 100 degrees Fahrenheit to 400 degrees Fahrenheit.
So if your industry application environment is continuously exposed to high temperatures, especially in the aerospace, automotive, or medical industries, this is the right type of silicone material to consider.
Superior Physical Strength
Platinum-cured silicone is also known for its superior strength and the ability to resist high pressures.
Again, it is fatigue-resistant and does not develop cracks even after a long period of use.
All these make its application popular in biotechnology fluid-handling facilities, aerospace, automotive, and medical industries among others.
Excellent Flexibility
Another property that you will find amazing is the incredible flexibility of additional cure silicone.
Depending on requirements, you can easily transform or mold it into any shape and size without affecting its strength or durability.
This makes it a great choice for some of your projects where flexibility and high-strength-to-volume ratio are required.
UV and Ozone Resistant
Another property is the ability of platinum-cured silicone to resist UV radiation as well as ozone.
So, if you are thinking of a material that is best suited for outdoor applications even in exposed locations, this is the right silicone to go for.
High Elongation Rate
You can easily stretch platinum cure silicone because of its excellent elongation rate.
you do not have to worry about it either breaking or tearing. Even in a stretched condition, it remains strong.
This, no doubt makes it highly suitable in application areas where you desire durable parts with excellent strength and durability.y
Resistant to Chemicals
If you expose platinum-cured silicone to different types of chemicals like acids among others, its properties will not be affected.
Its resistance to chemicals is excellent making it the silicone of choice for harsh chemical environments.
Addition Cure Silicone | Platinum Cured Silicone – Processing
Platinum Silicone – Process Phases
To manufacture platinum-cured silicone, there are three major processes involved.
Phase 1: Base Preparation
You need to get a base silicone rubber. This requires that you combine silicone polymers with a curing agent.
Phase 2: Mixing Process
You then mix your base silicone rubber with a small quantity of platinum catalyst to form platinum silicone.
Phase 3: The Curing Process.
To enhance the strength and durability of platinum-cured silicone, you initiate heat treatment to accelerate the curing process.
Platinum-cured | Addition Cure Silicone – Process Stages
The following are the general stages in the manufacturing process of platinum silicone:
Stage 1: Preparation of Raw Materials
In this initial stage, you must prepare all the ingredients needed for your additional cure silicone material.
Your main ingredients will consist of polydimethylsiloxane, a silicone elastomer, and curative ingredients.
You also require other necessary ingredients such as silicone oil, colorants, accelerators, fillers, and other suitable additives.
Stage 2: Compounding
In the compounding stage, you need to mix and heat your already prepared ingredients. All your ingredients should be a homogenous mixture.
Stage 3: Extrusion Molding
With your homogenous silicone mixture ready, you begin your extrusion molding process to produce the desired complex silicone shape using an extruder machine.
Stage 4: Curing Post-Curing
After a successful extrusion, you add a small amount of platinum to the silicone as a catalyst. This will initiate a chemical reaction to harden your silicone product.
https://youtu.be/xDoRGrMoE90?si=anTy1iMxVLFebPHT
Step 5: Post-Curing
To ensure that your addition cures silicone cures effectively, you need to take it through a heat-treatment process.
You can leave it in an oven for a specified duration.
Stage 6: Quality Control (QC) inspection
After the silicone is cured, you visually inspect it for quality and consistency. You also measure it for any inconsistencies in size or shape
Stage 7: Packaging
After your platinum-cured silicone is approved to be of the desired quality, it is ready for packaging and delivery to the customer.
Benefits and Applications of Platinum-Cured Silicone
Platinum Cure Silicone – Applications and Benefits
Building and Construction Industry- Sealing
Because of its strength, resistance to harsh weather conditions, and good adhesion properties, platinum-cured silicone will perfectly serve you as a tough and durable seal in the building and construction industries.
In areas that may be prone to moisture such as bathroom windows, platinum cure silicone is the perfect silicone sealant you require. This is because of its superior resistance to mold and mildew.
Automotive Industry
Due to its resistance to extreme temperatures and exposure to chemicals, you will find platinum-cured silicone widely used in the automotive industry as a sealant in engines to replace rubber seals or gaskets.
There are also special blends of platinum-cured silicone you can use as a protective coating for the vehicle’s exterior.
Aerospace Industry
The Superior properties of platinum cure silicone such as strength, resistance to extreme temperature, high pressure, and resistance to UV and ozone make its application popular in the aerospace industry. So, you will find it commonly used in various parts of aircraft or satellites as sealants
Medical Sector Applications
Platinum-cured silicone is non-toxic with biocompatible properties. Therefore, it is the ideal material for the medical and pharmaceutical industries.
For instance, in the pharmaceutical sector, you find platinum-cured silicone hoses used to safely transfer fluids from one tank to the other during drug manufacturing processes.
Further, because platinum-cured silicone is resistant to chemicals including body fluids, you will find its application in the manufacture of medical implants.
As you may be aware, medical instruments require maximum protection from extreme external conditions or exposure to harmful chemicals, or bacteria.
That is why platinum-cured silicone also finds application in creating a protective layer on some of their surfaces.
This helps in prolonging their durability while keeping them safe from possible contaminations.
Seals and Gaskets
For strong and durable seals and gaskets with enhanced adhesion properties and resistance to extreme temperatures, platinum-cured silicone is the perfect choice in many industries.
What is great is that you can create or order custom platinum-cured seals resistant to high temperatures, pressure, or vibrations.
Custom Manufacturing – mold-Making
If you need to create a custom mold for your manufacturing business, additional cure silicone is a perfect material to consider.
It is a cost-effective option for you to create molds with complex and high-precision shapes.
Further, you can use the mold even in wet environments because of its high resistance to molds and mildew.
Adhesives Industry
If you are in the Adhesives Industry, then the superior adhesion properties of platinum-cured silicone make it your ideal adhesive material.
The silicone forms an excellent weatherproof bond between a variety of external materials ranging from glass, plastics, and metal structures.
Coating
Platinum-cured silicone is used to coat a wide range of surfaces as protection against harsh environmental conditions such as moisture or extreme temperatures
Additionally, it has excellent adhesion properties. Therefore, you can use it to coat a variety of surfaces, including metal, plastic, and glass.
It is also resistant to UV radiation, making it ideal for your outdoor coating needs.
Advantages & Disadvantages of Platinum Cured Silicones
Platinum Cure Silicone – Advantages
Cost-Effective For Bulk Production
If you focus on bulb production of platinum cure silicone parts or materials, platinum-cured silicone is an economical option to consider. This is mainly because of its low cost in material and tooling requirements.
Long-Lasting /Durability
Platinum-cured silicone is highly durable. This is because of its excellent resistance to harsh conditions including high temperatures and UV radiation.
Again, with its resistance to moisture and chemicals, you can be confident that will serve you for longer with no degradation.
High-strength and Lowest Long-term Shrinkage
Platinum-cured silicone is known for its high strength and stability making it your perfect choice in application areas where such properties are required.
Further, because it has the lowest long-term shrinkage rate than any silicone, the shape of your created products such as molds or other items will not change over time.
This property makes it a suitable choice if dimensional stability is critical in your application areas.
Resistant to High Temperature and Chemicals
You will find additional cure silicone highly suitable for applications in high-temperature environments or where chemically-intensive applications are desirable.
For instance, its different forms such as its silicone tube type will serve you under a wide range of temperatures and will remain resistant to different chemical fluids including acids and alkalines.
It Is Non-Toxic
In addition, cure silicone is also non-toxic. Therefore, it does not contain any hazardous chemicals. This makes it your safe silicone of choice where food contact is necessary.
Excellent Bonding Properties
When you are looking for a reliable bonding solution for either your medical devices or electronic components, platinum cure silicone will not disappoint.
It is highly adhesive with excellent bonding properties.
Outdoors Application – Resistant to UV Radiations
You can use platinum-cured silicone outdoors without worrying about its degradation by UV radiation. Thanks to its resistance to UV radiation and other weather elements including ozone.
Cleaning Ease
You will not find cleaning a component made of platinum cure silicone a sweaty job. It is easy to clean and maintain.
All you need is to clean it with a dump piece of cloth and a suitable cleaning solution to keep it spotless and shiny in no time.
So, if you have areas that demand frequent cleaning, platinum-cured silicone sheets will save you time and energy.
Application Flexibility
Platinum-cured silicone is extremely flexible in terms of application areas.
For instance, you can choose it as your outdoor window or door glass sealant, or as an insulation sealant in electronic devices
You can also use it to create molds of different shapes and sizes. Its application areas are endless!
Platinum Cure Silicone – Disadvantages/Limitations
Apart from the disadvantages, here are some of the limitations of Platinum-cured silicone that you should take note of
Cost Limitation
Platinum-cured silicone will cost you more compared to other silicone types such as peroxide-cured silicone. Why?
Because platinum metal, which is the required catalyst for its manufacture is a rare and precious metal that is costly to get.
Its production process also results in a cleaner and purer silicone that is worth spending an extra buck on.
High Viscosity – Difficult to Work With
If you are working with addition-cured or platinum-cured silicone, you will find it challenging especially when trying to apply it evenly to seal a joint. This is so because it is highly viscous.
So to avoid any possible errors or leaks, you must be extra careful when working on a joint.
Difficult To Remove
When undertaking your platinum cures silicone seal repair, you will not find the process a smooth sail.
This is so because Platinum-cured silicone strongly adheres to surfaces exposing them to damage risks during its removal.
In an attempt to remove them, you may resort to using chemicals that still, may not be friendly to your joint surfaces.
Short Port Life
Anytime you are working with platinum cure silicone, you must quickly give your project the best shot in the shortest time possible because it has a short port life.
Any delays during application may result in low-quality results.
Require High Curing Temperature
Unlike other silicone types, you will require higher temperatures for your platinum-cured silicone to cure effectively. This will automatically bite into your time and expenditure on heating power requirements.
Curing Process Odor
During the curing process of addition cure silicone, a strong odor is produced. This may prove hazardous if you are not in a well-ventilated space.
High Risk of Contamination – Curing Inhibition
Certain chemical contaminants can permanently inhibit the curing process of platinum-cured silicone.
So, some of the notorious contaminants you must keep away from your curing area are organic sulfur compounds and organotin compounds,
Conclusion
Platinum-cured silicone is a leading flexible and highly reliable premier-grade silicone enriched to fulfill your wide range of industry applications.
Its superior properties make it a perfect choice especially if you are keen on selecting a long-lasting top-quality silicone material with stable performance in different conditions
As a high-purity silicone that is non-toxic, and resistant to extreme temperatures and pressure, it is the most ideal choice for healthcare sector applications.