PVA Water-Soluble Film: How Is It Produced?

PVA water-soluble film dissolves easily in water and breaks down fully. OECD 301B tests show it degrades over 60% in just 28 days. Because of this, it’s widely used for packaging in many industries. It finds application in agriculture, manufacturing, and packaging, significantly enhancing production efficiency. This article explains how PVA water-soluble film is made. It covers the techniques involved, giving you a better understanding of this material.

What is the raw material for PVA water-soluble film?

Polyvinyl Alcohol

Among the materials used in PVA film production, the primary component is polyvinyl alcohol (PVA). This is a white, stable, water-soluble polymer. Polyvinyl alcohol has hydroxyl groups that react with water. This forms hydrogen bonds, which make it soluble. The vinyl acetate residue group in PVA is hydrophobic. This means it lowers water solubility. Consequently, the degree of hydrolysis for polyvinyl alcohol is typically around 88%.

Starch

To further enhance the water solubility of PVA film, starch is incorporated into the raw material. Starch contains hydrophilic hydroxyl groups, which improve the film’s solubility. Starch also works as a hydrophilic modifier. This cuts the cold water dissolution time to under 30 seconds (BestY Pack lab data).

Additive	Function
Plasticizer	Improves toughness and die-cutting performance of PVA water-soluble film
Defoamer	Prevents foam generation during film production, ensuring smooth surface
Surfactant	Reduces surface tension of film molecules, accelerating water dissolution
Drying Aid	Accelerates drying and curing in PVA water-soluble film production, enhancing efficiency
Release Agent	Facilitates release operation in casting process, reducing error rate
Anti-blocking Agent	Prevents high-temperature adhesion of finished PVA water-soluble film

PVA Water-Soluble Film Production Process

The production of PVA water-soluble film employs solution casting technology, primarily comprising the following steps.

Dissolving PVA in Water

The production of PVA water-soluble film first requires mixing polyvinyl alcohol with water to form a solution. The critical aspect of this stage lies in precisely controlling the PVA proportion to ensure the film’s water solubility. Additives are also incorporated into the solution at this point.

Casting and Coating

The solution is spread onto a smooth surface or coated onto a roller, with careful control of temperature and humidity. This ensures uniform film thickness, achieving the desired performance characteristics.

Drying and Curing Processes (Thermal Treatment), Peeling

Following film formation, further drying is essential to achieve complete solidification. This stage is critical for the film’s mechanical and physical properties. Curing enhances stability, tensile strength, and flexibility.

Winding the finished product

Upon completion of curing, the film must be carefully wound onto reels. Alternatively, it may be slit into specific shapes according to customer requirements. Throughout this process, strict control over film thickness and quality is maintained.

PVA Film Manufacturing Techniques

PVA film is made using two main methods: solution casting and melt extrusion. Sometimes, blow molding is also used. The properties of films produced by these differing techniques vary.

Solution Casting: Solution casting technology is used to produce water-soluble PVA films. The fundamental production process, as described above, involves dissolving PVA in water to form a solution. Heating and drying subsequently take place, culminating in film formation.
Melt Extrusion: Suitable for industrial-scale PVA film production. Unlike solution casting, this method does not require dissolving PVA in water. PVA melts at high temperatures. Then, it cools and solidifies into PVA film. This process creates film with specific properties efficiently.
Blow Moulding: Less commonly employed but highly efficient. Melted PVA is expanded into a bubble through a tubular die and wound onto a reel. This process is well-suited for producing PVA film for packaging bags.

PVA Film Quality Inspection

Following production, PVA film undergoes rigorous quality inspection. Particular attention is required for PVA film used in medical and food applications.

Before PVA film production:

We select premium raw materials through multiple screening stages. Formulation ratios undergo repeated validation to ensure film properties meet customer requirements. Machinery functionality is verified to minimize operational errors.

During PVA Film Production:

Throughout the manufacturing process of PVA water-soluble film, we implement continuous online monitoring. Specialized equipment checks the accuracy of parameters at every stage. This ensures precise solution concentration, environmental temperature, humidity, and pH levels.

Post-Production PVA Film:

We conduct a series of simulated scenarios to test the film’s performance under real-world conditions rigorously. Quality certification is obtained through professional institutions, ensuring that each batch complies with industry standards.

Types and Applications of PVA Water-Soluble Film

Type	Description and Applications
Water-soluble laundry bag	Capable of packaging large quantities of soiled laundry with a barrier rate >99.9% (against Staphylococcus aureus, per third-party test report). Suitable for laundry packaging in hotels and hospitals.
Water-soluble transfer film	Rapidly dissolves in water to transfer textures; suitable for the printing and design industries.
Water-soluble embroidery film	Surface texture stabilizes threads; suitable for the embroidery industry.
Water-soluble heat-shrinkable film	Shrinks upon heating; suitable for efficient packaging.
Water-soluble release film for marble	Strong release properties; suitable for artificial marble.

choose BestY Pack

BestY Pack is a National High-Tech Enterprise with 15 years of experience in PVA film. We develop and produce for over 500 clients worldwide. We pursue biodegradable packaging solutions, offering bespoke manufacturing services tailored to your needs. Our PVA water-soluble film stands as one of our premium products, boasting excellent performance. It fulfills the requirements for rapid water dissolution and functional needs.

We have a lot of production experience and focus on our customers. We are ISO 9001 certified, so we guarantee top-quality products. We also want to share our expertise on PVA film. This will help you understand it better and choose the right PVA film products for your needs.

PVA Water-Soluble Film possesses excellent water solubility, dissolving rapidly in water. Dissolution doesn’t mean degradation. PVA remains as tiny particles in the water. In this state, PVA readily causes environmental pollution, as it is particularly prone to settling in sewage systems and subsequently re-entering the natural environment. These minute PVA particles are difficult to collect and treat, posing threats to both the global environment and human health. Nevertheless, once PVA is collected centrally, it undergoes specialized processing to degrade into water and carbon dioxide, thereby reducing environmental harm.

When selecting PVA water-soluble film, multiple factors must be considered in relation to the specific application scenario.

Firstly, the required dissolution temperature and rate determine the film’s water solubility. We modify the production formulation to ensure it meets your specific usage conditions.

From a manufacturing perspective, PVA water-soluble films are produced using either the blown film or cast film process. Should you require higher film thickness or heat resistance, cast film is the recommended choice.

We offer bespoke production of soluble PVA film. Should you require this service, please contact us promptly. Our specialist team will devise an optimal solution for you.

Firstly, challenges in raw material procurement. Sourcing polyvinyl alcohol is challenging. This is due to global trade relations, climate factors, and other variables. These manifest as price volatility and shipping delays.

Secondly, maintaining consistency in large-scale production poses significant difficulties. Even with advanced production equipment, making water-soluble PVA film needs careful formulation at every stage. Achieving uniformity across bulk orders remains a key challenge.

Additionally, environmental sustainability presents considerable challenges. The production process generates various waste liquids and materials. Without prompt professional treatment, these by-products can cause severe environmental pollution.

Hello, customers

My name is Jack Yu. I am the Business Manager at BestY Pack Plastic Products. My areas of expertise include film packaging, cold chain transportation packaging, and shrink products. Additionally, our factory manufactures protective gloves, and I can provide you with professional solutions to help you increase your market share and enhance consumer trust.

Email: ﾠjackyu@bestypack.com
Tel: +86 18368319351

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