FOAM RUBBER SERIES

Open cell  Semi-close cell  Close cell

Constantly and improve the new materials & technology for the application & needs of different industry fields


 

Manufacturing history

Foam rubber was first produced in 1929 by Dunlop Rubber researcher chemist Eric Owen using whipped latex. In 1937 isocyanate based materials were first used for the formation of foam rubbers, after World War II styrene-butadiene rubber replaced many natural types of foam. Foam rubbers have been used commercially for a wide range of applications since around the 1940s. The industrial needs of our 21st century world are far more advanced and varied than they have ever been. Many industries need special types of products for their specific applications. Foam sponge rubber is one such special product. As an alternative to more commonplace solid rubbers, sponge rubber products are used when better rates of compression and flexibility are needed. Also known as cellular rubber, it comes in open cell and closed cell variations. Foam sponge rubber was discovered by accident in 1937 by the German chemist Otto Bayer. The type of sponge rubber developed was in the form of neoprene. Today, however, foam rubber sheets can come as neoprene, nitrile, EPDM, or even a blend of different rubber compounds. CASIS recognizes that sponge rubber is crucial for a large variety of applications, so we aim to make inventory the right kind of cellular foam rubber for your needs. Currently, EPDM-based foams make up over 46%, by weight, of the entire market for EPDM. The largest amount of EPDM is used by these industries: Automobile, construction, electronic, household appliances, noise and vibration reduction, and beauty. Automobile uses 27% of EPDM, and electronic uses 21%. Flexible foam is the leading material usage at 44% total volume, and rigid foam material at 28% of the market.


 

Classification and characteristics
The most important thing to realize is that foam sponge rubber is inherently different from its solid rubber counterpart. This difference is readily apparent in the cellular structures of both open cell rubber and closed cell rubber. This means that the material is perforated with air pockets throughout its body. Foam rubber is generally softer than regular solid rubber. In contrast, solid rubber has a molecular structure that is very closely packed together, which makes it a generally thicker and sturdier elastomer. Solid rubber tends to have a low compression rate. Foam sponge rubber, on the other hand, has a superior compression rate over solid rubber. Compression is the ability of an elastomer to revert back to its original shape after being manipulated by physical objects and pressure. As a result, cellular rubber can be great for use as seals and gaskets. However, there are a few key differences between the open cell rubber and closed cell rubber versions. The open cell variety has visible air pockets throughout its body. Its appearance is similar to household sponge items. This feature gives it a better compression rate, meaning that it will bounce back to its original form faster than closed cell sponge rubber. Also due to the visible open air pockets, it is a more porous elastomer that will allow liquids to pass through it easily. Closed cell sponge rubber products, however, are not porous. They do not have the same visible pockets that allow for liquids to pass through, meaning that it is well suited to repelling water. It is denser in comparison with open cell rubber and rebounds to its original shape at a slower rate. However, closed cell rubber is desirable when a better level of strength is required in your application. Foam sponge rubber has general characteristics that are shared between the open and closed cell variations. They each come in forms that have low, medium, and high rates of density, although the closed cell version tends to have superior rates of density overall. Both rubber foam types feature great levels of flexibility so that they can be adapted for a wide range of specialized uses.

Rates of polymerization can range from many minutes to just a few seconds. Fast reacting polymers feature short cycle periods and require the use of machinery to thoroughly mix the reacting agents. Slow polymers may be mixed by hand, but require long periods on mixing, as a result industrial application tends to use machinery to mix products. Product processing can range from a variety of techniques including, but not limited to spraying, open pouring, and molding.

• Material preparation Liquid and solid material generally arrive on location via rail or truck, once unloaded liquid materials are stored in heated tanks. When producing slabstock typically two or more polymers streams are used.

• Mixing Open pouring, better known as continuous dispensing is used primarily in the formation of rigid, low density foams. Specific amounts of chemicals are mixed into a mixing head, much like an industrial blender. The foam is poured onto a conveyor belt, where it then cures for cutting.

• Curing and Cutting After curing on the conveyor belt the foam is then forced through a horizontal band saw. This band saw cuts the pieces in a set size for the application. General contracting uses 4’x12’x2’’.

• Further processing Once cut and cured the slabstock can either be sold or a lamination process can be applied. This process turns the slabstock into a rigid foam board known as boardstock. Boardstock is used for metal roof insulation, oven insulation, and many other durable goods



Physical properties 

The main physical properties of foam rubber are generalized as being “Lightweight, buoyant, cushioning performance, thermal and acoustic insulation, impact dampening and cost reduction”.Crosslinking technology is used in the formation of EPDM based foams, including NBR, CR, PVC, PU, and TPE. Crosslinking is the most important characteristic in the production of foam rubber to obtain the best possible foam expansion and physical properties. Crosslinking is defined as chemical bonding between polymer chains, and is used for foam rubber manufacturing to stabilize bubble expansion, enhanced resistance to thermal collapse and improve physical properties.

Recycling

Due to the variety in foam rubber chemistries, it is difficult to recycle foam materials using a single method. Reusing slab stock foams for carpet backing is how the majority of recycling is done. This method involves shredding the scrap and bonding the small flakes together to form sheets. Other methods involve breaking the foam down into granules and dispersing them into a polyol blend to be molded into the same part as the original. The recycling process is still ever developing for foam rubber and the future will hopefully unveil new and easier ways for recycling.



Capacity
CASIS manufacturing various grades of sponge. Open cell/Close cell sponges have no connecting cavities, making them ideal for applications where water exclusion and sound and gas retention are important.  Open cell sponge has connecting cavities which make the sponge more compressible.  We have the capability to convert our sponge rolls into gaskets, pads and strips cut to any width to suit your requirements. Sponge is available either plain or self-adhesive backed. CASIS product range can be supplied in various formats, from Industrial block onto Split SHEETS to required thickness. The uncompromised traceability of our materials and color coding for our product range which includes EPDM open cell and Semi closed Cell EPDM, Chloroprene (CR), EPDM Blends, Sulfur Free (eco Friendly) EPDM – Special Fire Resistant Grades with US or Europe Homologations – EPDM/NBR etc … all designed to meet almost every need. 

Applications

Gaskets, barrier to moisture, dust proofing, vibration dampening, sealing, cushioning, packaging, sound deadening, insulation, gas retention. CASIS’s line of foam rubber sheets consists of a variety of different elastomers. This is to ensure that consumers can have the appropriate physical and chemical features of a specific elastomer for their application. We offer sponge rubber products that are made from EPDM, neoprene, nitrile, as well as blends of different types of rubbers. Each type of synthetic elastomer is meant to give your foam sponge rubber enhanced traits against oil, grease, increased temperatures, and environmental factors like UV rays and ozone. Thanks to their synthetic rubber content, foam cellular rubber is perfect for industrial applications.

Foam sponge rubber has been in use since World War II. Although it was an accidental development at first, it quickly proved itself to be a highly desirable component for use in heavy industrial applications. It played a part in World War effort back then and it still plays a part in global industrial landscape today. Foam sponge rubber has even been used outside the industrial field in the realms of commercial construction, medicine, and even fashion. People love the superior levels of flexibility and compression that foam rubber sheets offer. Available in different synthetic rubber options in both open cell and closed cell form, foam sponge rubber is the answer to your application’s requirements.