Often hailed as the knight in shining armor for fix-it-up projects, super glue has been a staple in toolkits worldwide for its superior bonding ability. This miraculous adhesive is known for its strength and speed, easily adhering to a wide array of materials, from broken ceramics to torn fabric. But have you ever wondered why super glue doesn’t stick to everything? This trusty sticky substance can’t affix to every surface we want it to. Let’s embark on a journey to unravel the mystery of what super glue does not stick to and why!
The Science Behind Super Glue
Before delving into what super glue doesn’t stick to, it’s crucial to grasp an understanding of the inherent science behind it. Super Glue, also known as cyanoacrylate, is a unique adhesive that begins to set as soon as it comes into contact with moisture. It then rapidly polymerizes in the presence of water (including humidity), leading to a strong and fast bond that is difficult to break. This process, known as anionic polymerization, results in the adhesive sticking firmly to the material’s surface.
Materials Super Glue Does Not Stick To
Despite its prowess, super glue isn’t the all-conquering adhesive we often perceive it to be. It encounters stringent resistance from certain materials, which can be grouped generally into the following categories:
Plastics
Certain types of plastics, like polyethylene and polypropylene, are resistant to super glue. These plastics have a high resistance to chemicals, which makes them a poor candidate for bond formation. Their surface lacks the polar molecules necessary for super glue to adhere.
Metals
While super glue can bond two metal pieces together, it’s generally not recommended. Metals are non-porous and don’t provide the conditions needed for super glue to adhere firmly. For a stronger bond, it’s advisable to use epoxy or a specialized metal glue.
Highly Non-polar substances
Substances with very low polarity or none at all, like oil, silicone, and Teflon, can resist super glue as these materials repel the adhesive molecules in super glue.
Wet Surfaces
Although super glue promptly polymerizes in the presence of water, ironically, it does not stick well to wet surfaces. Excessive moisture can hinder the effective application of super glue.
Why Won’t Super Glue Stick to Everything?
Just as a key perfectly fits its complementary lock, super glue requires specific conditions to effectively adhere. Though it reacts with moisture to create a bond, super glue does not stick to wet surfaces because an excess of water interrupts the bonding process, resulting in a weaker bond.
The key to understanding the limitations of super glue lies within the realm of surface energy. Super glue adheres best to surfaces with high surface energy – those that are easy to wet. Surface energy pertains to the excess energy at the material’s surface compared to the bulk of the stuff. A material with a high surface energy allows the adhesive to “wet out” (spread out) and form a strong bond.
Polyethylene and polypropylene plastics have low surface energy, making it difficult for the super glue to form a bond. These plastics repel the adhesive, resisting the wetting process.
Another factor is the nature of the substance. Highly non-polar substances like silicone and Teflon repel super glue by creating a surface tension that the glue molecules can’t penetrate.
How Can You Make Super Glue Stick to Resistant Materials?
While super glue does not naturally adhere to everyone, there are some tips and tricks you can adopt to improve the chances. Here are a few steps you can follow:
Clean Surface
Before applying super glue, ensure the surface is clean and dry. Dirt and grim can interfere with the bonding process. A clean surface also enables the adhesive to spread out evenly, optimizing the bond strength.
Score Surface
Scoring or roughening the surface can increase its surface energy, making it more amenable to super glue. This process creates little grooves and pits which gives the adhesive a better grip.
Use of Primers
Primers or adhesion promoters modify the surface of the material, promoting better bond formation. They can help increase the surface energy, allow for better wetting, and improve adhesion.
Choose the Correct Type of Super Glue
Not all super glues are made the same. Some formulations are designed to work better with certain types of plastics and metals. So, ensure you’ve picked the right adhesive for the job.
Super glue’s universal usefulness is undeniable, but it’s important to know its limitations to ensure successful adhesive applications. Though it might not stick to everything, knowing why it doesn’t and how to optimize its use can lead to far more effective business and DIY project results.
Frequently Asked Questions
1. Does super glue stick to everything?
Super glue typically bonds to a wide range of materials, but there are certain surfaces it may not adhere to. Factors such as surface texture, composition, and the presence of certain coatings or oils can affect the bondability of super glue.
2. What does Gorilla super glue not stick to?
Gorilla super glue is incredibly strong, but it may not bond well with surfaces that contain moisture or are particularly smooth, oily, or dirty. Materials like polyethylene or polypropylene plastics, Teflon, silicone, and rubber can also pose challenges for the adhesive.
3. Does superglue stick to plastic?
Yes, super glue can bond effectively with many types of plastic, including acrylic, polycarbonate, PVC, and ABS plastics. However, it may not work well with polyethylene or polypropylene plastics, which have low surface energy and may require specialized adhesives.
4. Does super glue stick to parchment paper?
Generally, super glue does not adhere well to parchment paper. Parchment paper is coated with silicone, which creates a non-stick surface. The silicone coating prevents the glue from creating a strong bond with the parchment paper.
