Vinyl chloride (CH2=CHCl) typically does not react directly with water under normal conditions. This gas, primarily used to make polyvinyl chloride (PVC), a material common in various plastic products, is hydrophobic and does not readily dissolve or chemically interact with water. However, exposure to high temperatures or catalytic conditions can lead to hydrolysis, breaking down into hydrochloric acid (HCl) and other compounds, albeit inefficiently and not of practical relevance. The environmental and health concerns with vinyl chloride relate more to its carcinogenic nature and potential to contaminate water through industrial leakage rather than direct chemical reactions with water.

PVC connectors play a crucial role in plumbing and electrical systems, serving as joints for sections of PVC pipe or tubing. The most common types include: 1) Couplings, used to connect two pieces of PVC pipe; 2) Elbows, which change the direction of the piping system at various angles (most commonly 45° and 90°); 3) Tees, that split the flow of the contents into two directions; 4) Crosses, used to connect four pipes; 5) Caps and Plugs, which seal the end of a pipe; 6) Unions, designed for easy disconnection and reconnection of the pipes for maintenance. Each type of connector serves a specific function, ensuring a secure and efficient pipeline system. For optimal results, choosing the right type of connector based on the specific requirements of the installation or repair project is essential.

Polyethylene (PE) and polypropylene (PP) are both common plastics with diverse applications, from packaging to automotive parts. Generally, PE tends to be less expensive than PP. This price difference can be attributed to PE's simpler polymerization process and the fact that it is produced in larger quantities worldwide, which scales down its cost. However, prices can fluctuate based on market demand, oil prices (as both are petroleum-derived products), and the specific type or grade of the polymer. Polyethylene is preferred for its flexibility and durability, making it ideal for products like plastic bags and containers. Polypropylene, while slightly more costly, offers higher melting points, making it suitable for applications requiring resistance to heat, such as microwaveable containers. Ultimately, the choice between the two materials depends on the intended application's specific requirements and the budget constraints of the project.