Polyethylene terephthalate (PET) is a polymer consisting of repeating units of ethylene terephthalate, created through a polymerization reaction between ethylene glycol and terephthalic acid. This thermoplastic is renowned for its robustness, transparency, and resistance to water and many chemical solvents, making it widely used in the manufacture of beverage bottles, packaging materials, and fibers for clothing. PET's recyclability is one of its most valuable properties, contributing to its widespread acceptance as an environmentally friendlier plastic option. It can be recycled into new containers, clothing, and even industrial products, demonstrating a versatility that underscores its significance in reducing plastic waste and conserving resources.

Yes, all nonpolar molecules experience London Dispersion Forces (LDF), which are a type of van der Waals force. These forces arise due to temporary fluctuations in electron distribution within molecules, leading to momentary dipoles that induce corresponding dipoles in adjacent molecules. The strength of London Dispersion Forces increases with the size and molar mass of the molecules. While nonpolar molecules lack permanent dipole moments that would give rise to stronger intermolecular forces like hydrogen bonding or dipole-dipole interactions, LDFs are universal and act between all atoms and molecules, making them the only intermolecular force present in nonpolar molecules. Consequently, these forces are crucial for understanding the behavior and properties of nonpolar substances, including their boiling and melting points.

It seems you're asking about doing "streaks with dye" on hair, correcting what appears to be a typo. Adding streaks or highlights with dye involves sectioning off parts of your hair to apply color selectively. Here are the basic steps:

1. **Choose the Right Dye:** Permanent dyes offer lasting color, while semi-permanent dyes are less damaging but fade over time.
2. **Section Your Hair:** Use clips to section off the hair you want to dye, leaving the rest untouched. Thin sections work best for subtle streaks.
3. **Prepare the Dye:** Mix the dye according to the instructions on the package.
4. **Apply the Dye:** Using a brush or applicator, apply the dye to the selected sections. Be sure to wear gloves to protect your hands.
5. **Time It Right:** Leave the dye in your hair for the amount of time specified on the package. This can vary depending on the desired intensity.
6. **Rinse and Condition:** Rinse out the dye with warm water, then use a color-safe conditioner to moisturize your hair.

For those new to dyeing hair, it might be helpful to watch tutorial videos or consult a professional to avoid damaging your hair.