The key difference between caulk and silicone is that we use caulk specifically for sealing joints whereas silicone is useful in many different areas including sealants, adhesives, lubricants, medicine, etc.
Both caulk and silicone are useful as sealants. The application of caulk is what we call “caulking”. Also, there are different materials that we can use for caulking. Silicone, on the other hand, has many applications apart from using it as a sealant. It is a silicone based polymer.
CONTENTS
1. Overview and Key Difference
2. What is Caulk
3. What is Silicone
4. Side by Side Comparison – Caulk vs Silicone in Tabular Form
5. Summary
What is Caulk?
Caulk is a material that we use as a sealant to seal the joints against leakage in various structures. Hence, when considering the use of this material, we can divide it into two parts as traditional applications and modern applications.
Traditional Applications
In traditional applications, caulking uses fibres of cotton and oakum (hemp fibre soaked in pine tar). This caulking was very useful with wooden vessels. We can fill this material into the seam (wedge-shaped) between planks. People do this with a caulking mallet and a caulking iron. Then we have to cover the caulking with putty or with melted pine pitch. We call this process as calefaction.
Figure 01: Caulking
Modern Applications
Modern uses of caulk are mainly in closing up joints in constructed structures. This can help the structures with thermal insulation, control of water penetration and it also reduces noise transmission. Also, the compounds that we can use as caulk material includes silicone, polyurethane, silyl-terminated-polyether or polyurethane and acrylic sealant.
What is Silicone?
Silicone is an inorganic material that we use as sealants, adhesives, lubricants, medicine, etc. We call it as polysiloxanes as well. It is the chemical name of this compound. Also, these are polymer materials that consist of repeating units of siloxanes. Typically, silicone is heat resistant and is a rubbery material. However, sometimes, we can find it in its liquid form as well, depending on the intended application. It is a good thermal and electrical insulator. Common compounds that we use in day to day life include silicone oil, silicone grease, silicone rubber, silicone resin, and silicone caulk.
Figure o2: Silicone Moulds
This compound can make watertight seals. However, it has a high gas permeability. This means, it is highly permeable to gases such as oxygen, which makes it useful in medical applications where we need more aeration. We can use silicone in the automotive field as silicone grease to act as a lubricant for brakes. It is also useful in coatings; provides surfaces with waterproofing ability. Since silicone is non-toxic and low-taint, we can use this compound where we need to make tools that come into contact with food. liquid silicone is useful as a dry cleaning solvent. Moreover, it is resistant to microbial attacks, which provides this material with a long shelf life.
What is the Difference Between Caulk and Silicone?
Although both caulk and silicone are useful as sealant materials, silicone has many more applications. Hence, the key difference between caulk and silicone is that we use caulk specifically for sealing joints whereas silicone is useful in many different areas including sealants, adhesives, lubricants, medicine, etc. Moreover, based on the type of material, the difference between caulk and silicone is that the caulk can be silicone, polyurethane, silyl-terminated-polyether or polyurethane and acrylic sealant while silicone is polysiloxane.
Summary – Caulk vs Silicone
Caulk and silicone are sealant compounds. But there are many other applications of silicone. Therefore, the key difference between caulk and silicone is that we use caulk specifically for sealing joints whereas silicone is useful in many different areas including sealants, adhesives, lubricants, medicine, etc.
Reference:
1. “Caulking.” Department of Energy. Available here
2. “Silicone.” Wikipedia, Wikimedia Foundation, 27 Sept. 2018. Available here
Image Courtesy:
1.”Caulking, USAF” (Public Domain) via Commons Wikimedia
2.”Silicone mold”By Pfehrman – Own work (CC BY-SA 3.0) via Commons Wikimedia