Technical Guide to Selecting and Using POLYVA PVA Film

Selecting the right POLYVA PVA film starts with matching the film’s properties to the end-use requirements. Hydrolysis degree, thickness, solubility temperature, and additives all influence performance. This guide covers key selection criteria, processing recommendations, storage, and troubleshooting.

Hydrolysis level is the most important parameter. 88% hydrolyzed POLYVA PVA film dissolves in cold water (below 20°C) and suits laundry pods or consumer products. 98-99% hydrolyzed film requires hot water (40-90°C) and is used for industrial or delayed-release applications. Molecular weight affects strength and dissolution speed; higher molecular weight generally gives stronger film.

Thickness typically ranges from 20 to 80 microns. Thinner films dissolve faster and cost less but may have lower puncture resistance. Thicker films provide better barrier and durability during handling. POLYVA offers standard and custom thicknesses.

Additives include plasticizers for flexibility, anti-block agents to prevent sticking, and sometimes colorants or UV stabilizers. Food-grade or pharmaceutical-grade films use approved ingredients only.

Processing POLYVA PVA film requires attention to temperature and humidity. Heat-sealing temperatures are usually 120-180°C depending on grade and machine. Excessive heat can cause sticking or incomplete seals. Form-fill-seal machines should have humidity control or dehumidifiers because the film absorbs moisture from air.

Storage guidelines: keep rolls at 15-25°C and below 50% relative humidity. Use original wrapping until needed. Avoid direct sunlight and extreme temperatures. Proper storage prevents blocking and premature softening.

Quality testing includes:

- Dissolution time in water at specified temperature

- Tensile strength and elongation (ASTM D882)

- Thickness uniformity

- Moisture content

- Residual vinyl acetate

POLYVA supplies technical data sheets with these values. Incoming inspection is recommended for critical applications.

Common issues and solutions:

- Film blocking: increase anti-block additive or improve storage humidity control.

- Poor seals: adjust temperature, pressure, or dwell time; check jaw cleanliness.

- Slow dissolution: verify water temperature and agitation; confirm hydrolysis grade.

- Brittleness: check plasticizer content and storage conditions.

Converters should run trials with POLYVA technical support to optimize machine settings. Many machines designed for PE require only minor adjustments for PVA film.

Customization is available. POLYVA can modify formulations for specific barrier needs, printability, or dissolution profiles. Minimum order quantities apply for custom runs.

By following these guidelines, users achieve consistent performance and minimize waste. POLYVA PVA film, when selected and handled correctly, delivers reliable results across packaging and industrial applications. Contact POLYVA for samples, data sheets, and application engineering support.