Polypropylene is a versatile and robust plastic widely recognized for its resistance to a range of chemical solvents, bases, and acids, including vinegar. The polymer structure of polypropylene is such that it does not react with vinegar, which is a dilute form of acetic acid. This non-reactive property is due to the chemical resilience of polypropylene, which can withstand exposure to many chemical substances without degrading or losing its integrity. Therefore, polypropylene containers are often used for storing vinegar and other acidic substances in both industrial and domestic settings. It's important to note, however, that while polypropylene is resistant to vinegar, its long-term resistance can be influenced by factors such as temperature and the concentration of the vinegar. Nonetheless, for standard applications involving storage or transport of vinegar, polypropylene is considered highly effective and safe.

Setting epoxy resin fast requires controlling several factors, including the type of epoxy, ambient temperature, and adding accelerants. Fast-curing epoxy formulations can significantly reduce cure time. Raising the surrounding area’s temperature to about 75-85°F can expedite curing, as epoxy reactions are exothermic and thus proceed faster at higher temperatures. However, excessive heat can cause issues like shrinkage or yellowing. Additionally, specific hardeners or accelerants designed for use with epoxy can speed up the process without compromising the quality of the final product. It's crucial to follow the manufacturer’s instructions regarding proportions and mixing to avoid unwanted results. Remember, increasing the speed of the curing process might reduce the working time, so plan accordingly.

To stop a leaking PVC joint, first, turn off the water supply. Clean and dry the area around the leak. Apply PVC primer around the joint to prepare the surface, then use PVC cement (or a specialized PVC leak sealant) over the leaking area, ensuring full coverage. Hold it in place for a few seconds to set. For a temporary fix, use epoxy putty or a rubber repair tape wrapped tightly around the joint. However, a permanent solution often requires cutting out the leaking joint and replacing it with a new piece using PVC couplings. Always follow the product instructions for the best results.