In the central control room of Chongqing Changshou Chemical Industrial Park, the dashboard paused for the last time, and a message "discharge qualified" came through the intercom. A few days later, a white resin bagged truck with Sinopec logo set off for a European port. In the same week, Anhui Wanwei High Generation PVA Optical Film Production Line was simultaneously promoted - China is leveraging the supply chain of polarizer core materials, which has been monopolized by overseas for 20 years, from both raw materials and film materials.

New line filling gap

Polyvinyl alcohol (PVA), known as the universal auxiliary material of fine chemical industry, is a fully biodegradable water-soluble polymer. From laundry bead water-soluble film, facial mask humectant, eye drops auxiliary material, to building mortar, textile slurry, to photovoltaic packaging film, liquid crystal polarizer base film, medical drug slow release carrier, it depends on its purity and alcoholysis degree grading. In the past, domestic optical film grade and pharmaceutical grade high-end PVA relied on imports for a long time. The proportion of imported optical grade PVA for polarizing films once exceeded 80%, and the price and delivery time were controlled by overseas giants.

The 50000 tons/year special PVA resin plant put into operation by Chuanwei Chemical has been successfully driven in one go, and the first batch of products are directly shipped to Europe. By adding to the existing production capacity, the total scale of the base has increased to 210000 tons per year, making it not only the world's largest high-end PVA production base for a single factory, but also ranking fourth in the world in terms of overall production capacity. All newly added production capacity is aimed at special tracks, while the existing 160000 ton production capacity is optimized synchronously, with a coordinated layout of general supply guarantee and high-end substitution.

Breaking down barriers in craftsmanship

High end PVA is difficult to achieve to two decimal places: alcoholysis degree, metal ion impurities, and a slight difference in molecular weight distribution will result in excellent polarization of the polarizer and render the pharmaceutical carrier ineffective. The project team has overcome the challenges of precise temperature control and batch stability, using independently developed alcoholysis and precision purification processes to increase the production efficiency of the device by 40% compared to older equipment, and benchmarking the indicators of mass-produced products against international mainstream.

The new line is also equipped with 4 sets of exhaust and wastewater recovery facilities, intelligent packaging, and full life cycle traceability systems, achieving high-end, intelligent, and green operation from feeding to palletizing. Nowadays, the PVA grades of Chuanwei have expanded from one in the early years to over a hundred, covering general textile and construction scenarios, and can also steadily receive orders for photovoltaic, optical film, and electronic grade high-purity materials.

Chain is more controllable

The color of a mobile phone screen is uneven, and the core is the polarizer, which is made of optical grade PVA film as its core substrate. In the past, this barrier was controlled by Japanese companies, while domestic panel factories grew in scale but were hindered by raw materials. The landing of Chuanwei's 210000 ton base directly fills the gap in domestic high-end PVA resin production, and enhances the independent risk resistance capability of key chains such as photovoltaics, electronics, and optical films; Relying on the Chengdu Chongqing location, the domestic delivery cycle can be compressed to within 3 days, which has significant advantages compared to overseas sea freight clearance of more than 30 days.

More importantly, the industrial chain echoes - Anhui Weixin High tech is promoting the production lines of 4.8-meter and 5.7-meter wide high generation PVA optical films at the same time, while Sichuan Weixin supplies high-end resins and Anhui Weixin focuses on optical film production. The core materials of domestically produced polarizing films are shifting from "whether they are available" to "whether they can be used". When high-end PVA is no longer priced at gold, the cost curve of downstream new energy, new displays, and biodegradable packaging will be rewritten.keywords:New energy information network

From the reaction kettle at the foot of Changshou Mountain to the European shelves, and then to the polarizing film production line of domestic panel factories, every step taken by this batch of white resin is a footnote for China Fine Chemicals to regain its voice.Editor/Yang Meiling