When designing or specifying components that will be made with rubber or plastic, engineers should consider not only basic performance requirements, but also how these materials will fare in various environments over time. Of course, it’s not always easy to identify which rubber or plastic material makes the most sense for a particular design.
PVC and silicone are two common materials used in a variety of parts. While both compounds provide specific benefits for an application, each material have different environmental and performance characteristics that can make one a better option than the other.
When it comes to deciding which is right for your parts, it’s essential to understand how they differ. In this article, we’ll address the differences in PVC and Silicone and why you would opt for one material over the other.
The Differences Between PVC and Silicone
Both PVC and silicone share many of the same properties, such as good elasticity over a wide temperature range, exceptional resistance to chemicals, and strong insulation qualities. However, there are some notable differences between PVC rubber and PVC plastic. When it comes to manufacturing parts, the following factors can determine whether PVC or silicone is right for your needs.
- Manufacturing process
- Better resistance
- Specific Temperatures
- Durability
- Cost
Manufacturing process
The main different between the two materials is that one is a synthetic rubber, while the other is a thermoplastic. Silicone is also known as polysiloxane and is made by extracting silicon, passing it through hydrocarbons, and mixing it with other chemicals to create a special rubber.
PVC stands for polyvinyl chloride and is a polymer made by chlorinating hydrocarbon polymers to produce vinyl chloride monomer. This polymer can then be further mixed with additives like plasticizers and colorants to turn it into different forms of rigid and flexible PVC plastic.
Material resistances
One key factor to proper material selection is to identify which compounds can survive in your intended environment. Resistance of PVC and silicone to various chemicals can be determined by their resistance ratings according to the American Society of Testing and Materials (ASTM) standards for plastics.
PVC is one of the more resilient materials, boasting a variety of resistances. PVC offer either excellent or very good resistance to acids, alkalis, UV, ozone, flame, aliphatic hydrocarbons, and other substances. PVC is also resistance to grease, oil, chemicals, and general weathering. These capabilities make PVC suitable for numerous applicating environments.
Silicone doesn’t offer the same level of resistances as PVC, but it does offer excellent resilience when it comes to weather, UV, ozone, flame, and steam. Manufacturers can also add special additives to increase silicone’s electrical conductivity, while the material enjoys low chemical reactivity in general.
Temperature requirements
While PVC offers a wider range of resistances, silicone shines when it comes to dealing with low and high temperatures. Silicone offers excellent thermal stability and some of the highest temperature resistance of any rubber materials, with a high temperature usage of up to 480 degrees Fahrenheit. In addition, silicone offers a low temperature usage between -60 to -150 degrees. This makes silicone an excellent option for household appliances, furnaces, and other applications that demand heat resistance.
While PVC products don’t perform at nearly the same level in terms of hot and cold resistance, they can work in some elevated temperatures and frigid environments. PVC is graded for usage in temperatures up to 140 degrees and as low as 5 degrees.
Physical durability and toughness
When designing rubber and plastic parts, the durability of different materials should be taken into consideration.
PVC offers a wide hardness range as it can be made in both rigid and flexible compounds. This range allows businesses to invest in a hardness that best suits your design. PVC is also very durable over long-term use and will not corrode over time, even with exposure to bad weather and other challenging conditions.
Silicone doesn’t offer the same level of durability as PVC, but it can be made with fillers that improve both its tensile strength and tear resistance. Silicone also offers good compression set for any applications where silicone products will need to bounce back after compression.
Cost
While performance needs are an essential part of material selection, businesses should also consider the overall cost of specific materials. PVC is the less expensive of the two materials because it requires less complicated production processes. Silicone’s manufacturing process is more complicated, which drives up its cost and increases product prices for consumers.
Of course, there is a difference between which material is less expensive and which is more cost-effective. If your application requires a specialty material like silicone, then it is by far the more cost-effective option as other compounds would fail and require regular replacement. It’s essential to weigh your overall performance needs – if two materials both meet your parameters, the less expensive one will be more cost-effective in the long run.
Find the Rubber Parts That Are Right for Your Business
Whether it’s PVC, silicone, or some other compound, choosing the right material may be difficult, but it is necessary to get the performance and durability you need. Timco Rubber is a custom rubber and plastic parts supplier that specializes in producing high-quality, high-performing rubber goods through individualized service and material knowledge.
At Timco, we are committed to helping you find the best, most cost-effective part solution for your business. Give us a call at 888-905-8066 or contact us online today to talk to our experts about your part needs.
