Inferior car paint protection film is susceptible to hydrolysis
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With the enhancement of people's awareness of the protection of original car paint, many people will now put a layer of car coating film after picking up the car.
There are many brands of car paint protection film on the market, and it is difficult for general car owners to distinguish between good and bad, and after a long time, inferior car clothing is more prone to hydrolysis. The car coating film, which was originally pasted to protect the car paint, turned out to be the culprit of destroying the car paint.
*Sourced from the Internet
The hydrolyzed car coating film is difficult to clean, and can only be torn by hand or with a scraper, and it takes two days for the two masters of the film shop to clean up.
Originally, it was a cheap car coating film, but now it costs more money to deal with the after-sales service, and some people joke that "just pasting the car clothing is full of joy, and the hydrolysis regrets it".
Why does hydrolysis occur?
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The cause of hydrolysis starts with the composition of TPU material.
TPU is a basic component of the car coating film, providing good light transmittance, toughness, and a solid barrier to prevent the car paint from being scratched and damaged, but there are also many types of TPU.
Synthetic TPU particles are mainly composed of polyols and isocyanates.
Polyols
Let's start with polyols.
The commonly used polyols for the synthesis of TPU are: polyester polyols, polyether polyols, polycarbonate polyols, polycaprolactone polyols, etc.
1. Polyester type and polycarbonate type
Due to the existence of ester groups that are easy to hydrolyze, polyester TPU is susceptible to the invasion of water molecules and molecular chain breakage, and the acid generated by hydrolysis can catalyze the further hydrolysis of polyester, resulting in poor water resistance and low cost of polyester TPU.
2. Polyether type
Polyether TPU, because the ether group of the soft segment is easier to rotate, has good compliance, superior low temperature performance, and there is no relatively easy hydrolyzable ester group in the polyether, and its hydrolysis resistance is better than that of polyether. However, the mechanical strength, oil resistance and heat resistance are relatively poor.
3. Polycaprolactone type
Polycaprolactone TPU is between polyester and polyether, with good comprehensive properties, excellent mechanical strength, oil resistance, chemical resistance, wear resistance and tear strength, good flexibility, superior low temperature performance, and no relatively easy hydrolyzed ester group, and its hydrolysis resistance is good. However, the price is relatively high, and it is often used for medical artificial organs and blood vessels.
Highlight the point
1. Polyester and polycarbonate with ester base, easy to hydrolyze.
2. Polyether with ether bond is the most susceptible to photodegradation and is not temperature resistant.
3. Polycaprolactone has the advantages of polyester and polyether at the same time, and does not have ester groups and ether bonds.
The car coats produced by non-polycaprolactone TPU are prone to degradation!
