There are two types of rubber available: natural and synthetic. Each retains varying physical and chemical properties that differentiates them from one another. Natural elastomers are organically produced from the latex sap of the rubber tree. On the other hand, synthetic types of rubber are made through monomers that derive from petroleum oil. While there is only one type of natural rubber, there are multiple types of synthetic rubber. Additionally, due to the petrochemicals used to create synthetic rubbers, they will be more durable than natural rubber. Despite the difference in material makeup and physical and chemical properties, both natural and synthetic types of rubber are elastomers, allowing them to provide a degree of flexibility and pliability in accordance with their durometer.
What are the Two Types of Rubber?
The two types of rubber are natural rubber and synthetic rubber. The main difference between the two types of rubber are their material compositions that affects their physical and chemical properties. Natural rubbers, as its name implies, is a natural material that is harvested from the sap of a tree. Synthetic rubbers are man-made types of rubber that are made from petroleum-based chemicals that give them enhanced properties compared to the properties of natural rubber. Natural elastomers are environmentally friendly and plant-based types of rubber that derive from the Hevea brasiliensis, or the rubber tree. It retains excellent properties, such as a high tensile strength, abrasion resistance, and a low compression set; however, natural rubber “has only moderate resistance to damage from exposure to heat, light and the ozone in the air” (sciencing.com). Due to this, natural elastomers will not be as durable as types of synthetic rubber. Unlike natural rubber, synthetic rubber is a man-made material that is made up of various petrochemicals, or petroleum-based monomers. In general, synthetic rubber “offers better resistance to abrasion than natural rubber, as well as superior resistance to heat and the effects of aging. Many types of synthetic rubber are flame-resistant, so it can be used as insulation for electrical devices” (sciencing.com). Despite their difference in properties, both natural and synthetic rubbers are extremely strong materials.
(a)What is the Most Flexible Rubber?
All types of rubber are flexible, but there is no one rubber that is the most flexible as factors, such as durometer and gauge thickness, affect its flexibility. As an elastomer, all types of rubber, whether natural or synthetic, will be very elastic and flexible. An elastomer is “any rubbery material composed of long chainlike molecules, or polymers, that are capable of recovering their original shape after being stretched to great extents—hence the name elastomer, from “elastic polymer” (Britannica.com). As elastomers, both natural and synthetic rubber will have a certain degree of flexibility and pliability no matter what their durometer ratings are, but their durometer rating will determine the material’s hardness and, therefore, their level of flexibility. The hardness of the material is one factor that affects rubber’s flexibility; however, another factor that affects its flexibility is its thickness. The thicker the rubber material is, the less pliable it will be making it stiffer and harder to bend. As elastomers, both synthetic and natural elastomers will all retain a degree of flexibility depending on its hardness and thickness.
(b) What is the Most Durable Rubber?
Due to the varying physical and chemical properties of rubber, there is no most durable rubber; however, synthetic rubbers in general will be more durable than natural rubbers due to the chemical compounds used to create synthetic rubbers. Natural rubber, although highly impact and abrasion resistant, will not be able to stand up to harsh environmental factors, high temperatures, or caustic chemicals as synthetic types of rubber. For example, due to natural rubber’s organic carbon-to carbon bonded backbone structure, it will be susceptible to damage caused by exposure to ozone. In addition, although natural rubber is resistant to most acids, salts, ammonia, and alkali chemicals, most other caustic solvents, such as chemicals, oils, and greases, can deteriorate the material. Furthermore, natural rubber also has a lower melting point of approximately 356 degrees Fahrenheit. Contrastingly, a synthetic rubber sheet is much more chemically, thermally, and environmentally stable than a natural rubber sheet. For instance, synthetic rubber, such as silicone, have an operating temperature range of -212 to +572 degrees Fahrenheit. This is due to the petroleum-based monomers that are used to create synthetic types of rubber. Synthetic rubbers are created through the polymerization of “isoprene (2-methyl-1,3-butadiene), 1,3-butadiene, and chloroprene (2-chloro-1,3-butadiene)” (chem.libretexts.org). Unlike natural rubbers, the polymerization of these compounds does not produce a carbon-to-carbon polymer backbone (the backbone structure found in natural elastomers) structure allowing synthetic rubber to resist degradation/aging caused by damaging environmental factors, such as UV rays, ozone, oxygen, and moisture.
(c) What is the Cheapest Rubber Material?
Post-consumer types of rubber, such as recycled and reclaimed rubber, are the cheapest rubber material due to the decrease in energy used to create these materials. Both recycled and reclaimed rubber materials are made of waste tire rubber which makes them both environmentally friendly materials as it uses non-biodegradable rubber to make new products – reducing the amount of space it takes up in our environment and landfills. These are cost-effective types of rubber because they do not require as much energy to produce compared to other natural and synthetic rubbers. For instance, “Scrap tires as a back-fill and cover material are also more cost-effective, since tires can be shredded on-site instead of hauling in other fill materials” (Wikipedia.org). Not only does the usage of old vehicle tires make these rubber variations an eco-friendly and cost-effective material choice, but it also makes for durable rubber materials. Case in point, “Generally, utilization of WTR [Waste Tire Rubber] as a filler for polymer composites noticeably reduces materials costs, while suitable modification/functionalization of WTR may significantly enhance the performance of plastics and rubbers” (sciencedirect.com). Recycled and reclaimed types of rubber, although the cheapest rubber materials, are also highly durable and outdoor friendly materials.
(d)What are the Types of Synthetic Rubber?
The types of synthetic rubber are silicone, EPDM, SBR, nitrile, neoprene, and thermoplastic rubbers, such as Santoprene. The first synthetic types of rubber were invented to be a stronger alternative to natural rubber, allowing them to provide better physical and chemical properties. One of the main differences between synthetic and natural rubbers is their environmental resistance. Synthetic rubbers will not be damaged when left outdoors and exposed to harsh outdoor factors, such as UV rays, ozone, oxygen, and moisture. Natural rubber, although moisture resistant, will be damaged when exposed to ozone in a phenomenon called “ozone cracking” which causes the material to crack and break. Each synthetic rubber offers their own unique properties that are ideal for specific applications. For instance, silicone rubber is known for its superior thermal stability and can withstand extremely high temperatures without melting and extremely low temperature without hardening and becoming brittle. On the other hand, synthetic nitrile rubber is highly resistant to greases/oils whereas these solvents can severely damage natural rubber.
What Type of Material is Silicone?
Silicone is a synthetic rubber material that is characterized by its superior high temperature operating range of up to +500 degrees Fahrenheit. Unlike natural rubber, silicone is an inorganic polymer meaning it has a unique silicon-to-oxygen bonded polymer backbone structure that gives it superior resistance properties and thermal stability compared to both natural and synthetic types of rubber. Due to this unique polymer backbone structure, a silicone synthetic rubber sheet retains superior thermal stability as well as excellent chemical stability. In addition, thanks to its thermal stability, a silicone synthetic rubber sheet can remain flexible at low temperatures rather than becoming hard and brittle as most rubber variations tend to do. For example, “Some properties such as elongation, creep, cyclic flexing, tear strength, compression set, dielectric strength (at high voltage), thermal conductivity, fire resistance and in some cases tensile strength can be – at extreme temperatures – far superior to organic rubbers in general…” (wikipedia.org). Furthermore, silicone rubber is available in three different grades: commercial, premium, and FDA. This allows silicone rubber to be used in almost any setting, even in applications that involve materials that are intended for human consumption.
(a)What Material is Similar to Silicone?
Thermoplastic rubber materials, such as Santoprene, are similar to silicone. A thermoplastic sheet is composed of both rubber and plastic materials. A thermoplastic sheet retains excellent environmental resistance properties as well as a low compression set and high temperatures. According to the Standard Method for Determining Continuous Upper Temperature Resistance of Elastomers, a thermoplastic sheet can stand up well against transient, or fluctuating, temperatures as high as 300 degrees Fahrenheit and continuous temperatures of up to 275 degrees Fahrenheit. Due to its high temperature resistance properties, “TPE is considered as an efficient and cost-effective alternative for latex, silicone rubber, and polyvinyl chloride (PVC) compounds” (omnexus.specialchem.com). Thermoplastic materials are similar to silicone as it retains the elasticity of elastomers while also being more heat resistant than most natural and synthetic rubbers.
(b.) Is Silicone Stronger than Rubber?
Silicone is stronger than rubber because, even though they are both elastomers, silicone has better resistance properties that leads to longer life in abrasive applications. Other natural types of rubber may be considered “organic polymers”, due to their standard carbon-to-carbon bonded polymer backbone structure. This makes them more susceptible to damage caused by damaging environmental factors and extreme temperatures. Although most synthetic types of rubber can stand up well against these damaging factors, they will not be as strong as silicone. Silicone rubber has a Si-O [silicon-to-oxygen] bonded polymer backbone structure that gives it better heat resistance, chemical stability, electrical insulation, abrasion resistance, and resistance to damaging environmental factors (omnexus.specialchem.com). Silicone has an extremely wide operating temperature range of -103 to +500 degrees Fahrenheit. Silicone products are also highly chemically stable materials and have been used in applications where they are exposed to caustic chemicals, such as acetic acids, ammonia gas, and sodium sulfate. Silicone is superior to rubber as it can remain flexible in low temperatures and will not be susceptible to embrittlement as natural rubbers are likely to experience.
(c) Is Elastomer the Same as Silicone?
Elastomer is the same as silicone because silicone is an elastomer. An elastomer is “any rubbery material composed of long chainlike molecules, or polymers, that are capable of recovering their original shape after being stretched to great extents…” (britannica.com). Both natural and synthetic types of rubber are elastomers and will offer a certain degree of flexibility depending on its durometer. Silicone is a synthetic elastomer that is characterized through its wide operating temperature range as it can remain flexible throughout a wide range of high and low temperatures. Silicone can withstand a wide range of high and low temperature from as low as -103 degrees Fahrenheit to as high as +500 degrees Fahrenheit. Even at temperatures as low as -103 degrees Fahrenheit, silicone will remain flexible and will resist cracking caused by embrittlement.
What is the Raw Material for Rubber?
The raw material for rubber is natural latex sap and the raw material for synthetic rubber is petroleum oil. natural and synthetic types of rubber are each made using two separate raw materials that give each material their own physical and chemical properties. Natural elastomers are organic materials that are harvested from the rubber tree. The latex sap is then put through its production process that combines the latex sap with strengthening agents. Due to this, natural elastomers are environmentally friendly and biodegradable materials. The main raw material used to make synthetic types of rubber derive from petroleum oil. This gives synthetic rubber better and stronger physical and chemical properties compared to those of natural elastomers. Case in point, “They are ‘tailored’ to provide particular properties such as oil resistance, flexibility at extremes of temperature, resistance to ozone, etc., and therefore cannot be regarded as capable of replacement by natural rubbers although in some respects synthetics can be used in place of natural” (environmentalpollution.in). This makes synthetic types of rubber nonbiodegradable, yet physically and chemically stronger than natural elastomers.
(a)How Do You Make Natural Rubber?
You make natural rubber by harvesting the latex sap from the rubber tree and putting it through a solidifying process to create a solid material. Natural rubber is a naturally harvested material that derives from the Hevea brasiliensis, or the rubber tree. It is an environmentally friendly variation of rubber that is harvested through a process called “tapping”. Tapping is not harmful to the rubber tree as angled cuts are intricately and carefully made so that the tree can be wrapped back up to heal for future harvests. Once the liquid latex material is collected, ammonia is added to the liquid latex material to prevent it from hardening prematurely. It is then put through the process of coagulation which thickens the material into a clump (Britannica.com). Finally, the material must be dried and solidified for use. To produce a solid rubber material, the liquid raw material is often vulcanized, the process of heating the material with sulfur, to create a strong and solid rubber material.
Both natural and synthetic rubbers are resilient and elastic materials that are differentiated by their chemical makeup. The raw materials that makeup these types of rubber are the determining factors of their physical and chemical properties. Natural elastomers retain a high tensile strength, a low compression set, and are highly abrasion resistant; however, they will not function well when exposed to damaging environmental factors, including UV rays, ozone, oxygen, and moisture. Contrastingly, a synthetic rubber sheet can stand up well against these outdoor factors while also being stronger and more chemically and thermally stable with excellent chemical resistance and high temperature resistance.