The tensile strength of Polyvinyl Chloride (PVC) varies depending on its type and formulation. Generally, rigid PVC has a tensile strength ranging from 40 MPa to 75 MPa. This range can be influenced by additives, plasticizers, and other modifiers. For instance, unplasticized PVC (uPVC), which is commonly used in construction applications such as pipes and window frames, typically exhibits higher tensile strengths at the upper end of this spectrum. Conversely, flexible PVC (fPVC), which contains plasticizers for enhanced flexibility, usually has lower tensile strength. It's important to note that these values are approximate and can vary significantly based on specific product formulations and testing conditions. For precise applications, consulting material data sheets or contacting manufacturers directly is recommended to obtain accurate and reliable tensile strength values.

Lecithin is not a polymer in the traditional sense of large molecules composed of repeating structural units. It is a complex mixture of phospholipids, glycolipids, and triglycerides. Lecithin primarily contains phosphatidylcholine, along with other components such as phosphatidylethanolamine and phosphatidylinositol. These are not polymers but are rather individual molecules with specific functions, particularly in cell membrane structure and function. Phospholipids like those in lecithin have a defining feature: a hydrophilic (water-attracting) head and a hydrophobic (water-repellent) tail, which is crucial for their role in biological membranes but does not classify them as polymers, which require long, repeating chains.

The international price of polypropylene, a thermoplastic polymer used in a wide array of applications from packaging and textiles to automotive parts, fluctuates based on several key factors. These factors include crude oil prices, as polypropylene is a derivative of petroleum, demand and supply dynamics in major markets, and geopolitical events that may impact the global supply chain. Prices can also vary significantly across different regions due to transportation costs, import tariffs, and local market demands. For instance, emerging markets with growing manufacturing sectors might experience higher demand and hence slightly higher prices. Additionally, technological advancements and recycling efforts can impact the long-term pricing trends by potentially reducing the reliance on virgin polypropylene. Keeping a keen eye on market reports and indices from reputable sources can provide the latest pricing trends. It's crucial for businesses relying on polypropylene to stay informed about these factors to manage costs effectively.