For synthetic resins, are the raw materials you use up to standard?

The raw materials should be determined based on the actual conditions of the facility, without necessarily adhering to national standards. If the facility’s purification system is efficient, stricter requirements regarding impurities in the raw materials can be applied. As catalyst performance improves, different specifications for the raw materials may become necessary. Additionally, if the reaction system can tolerate a certain level of impurity in the raw materials, then those specifications can also be relaxed, as long as it does not affect the quality of the product. For example, in the production of polypropylene, it is generally required that the propylene used be of polymer-grade with a purity of 99.5%; in practice, however, the purity of the propylene entering the reactor is around 95%. When propylene is in short supply, propylene with a lower purity can still be used. The propylene produced by Anqing Petrochemical is mainly used for the production of acrylonitrile, and its purity is only 98–99%; sometimes it has to be used despite this, as it does not significantly affect product quality, but it increases catalyst consumption and reduces yield.

Thank you both! If it’s just a matter of product purity or content, it’s still manageable – just reduce the price and accept it ； But often, the raw materials have a darker color, a stronger odor, and higher processing requirements, etc. Ugh, sometimes there’s really no choice – in many cases, I have to make do with them anyway. ] This post was last edited by lovelyiyou on 2007-12-12 20:32 ]

We also use substandard products occasionally, but only in small quantities; mostly, they are purchased on an ad-hoc basis by the procurement department when there is an urgent need during production. However, this has little impact on the quality of the products produced, with only slight differences in cost. This is how I view your problem: if you have the means and a sufficient supply of high-quality materials in stock, you can use them in appropriate proportions, ensuring quality while reducing costs. It also helps to minimize variations in the quality of the final products caused by differences in the raw materials used. For customers, it’s easier to accept consistent product quality rather than ten batches of top-quality products mixed with one batch of lower quality, as they don’t need to adjust their usage conditions to accommodate changes in the raw materials. We also use our own recycled monomers in the production process

The impact of impurities in the raw materials varies depending on the components; some only affect the yield of the catalyst, while others affect the quality of the product. I’m facing a problem now: due to the high presence of impurity components in the raw materials, the product lacks sufficient rigidity, and it’s impossible to determine which specific component is causing this issue. It’s really frustrating:Q

Yes, sometimes it is impossible to predict accurately in advance what impact the use of substandard raw materials will have on the downstream products, especially in large-scale production, where it is even more difficult!

If it has a significant impact on product quality, it is most likely due to high levels of ethylene or other dienes, which affect the product quality after participating in the reaction

The process requirements for many production facilities vary quite significantly. High-pressure polyethylene can tolerate lower-quality raw materials to a greater extent, while most PP and PE applications require very high standards of raw material quality. When the raw materials do not meet these standards, it leads to excessive operation of the purification systems before the reaction takes place, a decrease in the activity of the reaction catalysts, and a decline in product quality