ISO 11468:1997 PDF

Overview

ISO 11468:1997 - Plastics - Preparation of PVC pastes for test purposes - Dissolver method - specifies a reproducible laboratory procedure for preparing PVC pastes (plastisols) using a mechanical dissolver. The standard defines apparatus, mixing vessel sizes, operating practice and documentation needed to produce pastes used to characterize PVC resins (rheology, viscosity and batch-to-batch consistency).

Key topics and technical requirements

• Purpose: Preparation of PVC pastes from polymerized vinyl chloride for rheological testing and to establish consistency between deliveries.
• Apparatus: A motor-driven dissolver with a coarsely toothed stainless-steel disc, suitable mixing vessels (single- or double-walled) and an external cooling system (water-cooled double-walled vessel recommended). Disc teeth are inclined (~30°) and alternate vertically. Vessel/disc sizes and typical paste masses are specified (examples: disc diameters 40/50/80 mm; vessel diameters 65/80/120 mm; paste amounts ~200, 400, 1 500 g).
• Operating parameters: Condition resin and plasticizer at 23 °C (±1 °C). Initially wet the resin into the plasticizer manually, then mix in the dissolver for defined intervals (typical cycle includes two mixing intervals of about 150 s each, with a manual scrape between). Maintain constant spindle speed during mixing (speed varies with dissolver size). Prevent paste temperature exceeding 35 °C; use external cooling to remove frictional heat.
• Materials & measurement: Use stainless-steel components; weigh ingredients accurately (weighing to 1 g; balance accuracy 0.5 g recommended). If paste is for viscosity measurement, de-aerate under partial vacuum (example 700 Pa) until foam collapses and hold for ~5 minutes.
• Reporting: Paste-preparation report must reference ISO 11468, identify the PVC resin, record paste formulation, end-of-mix temperature, preparation date and any deviations.

Applications and who uses it

• Quality control laboratories verifying PVC resin rheological properties and batch consistency.
• R&D and materials testing labs preparing standardized plastisols for viscosity and processing studies.
• PVC resin manufacturers and converters needing reproducible paste preparation for internal specification testing.
• Third-party testing bodies and certification labs applying standardized procedures for comparative testing.

Keywords: ISO 11468, PVC pastes, dissolver method, plastisol preparation, PVC rheology, paste preparation, viscosity measurement, plastics testing.

Related standards

• ISO 291 - Standard atmospheres for conditioning and testing (conditioning at 23/50).
• ISO 1060-2 - Homopolymer and copolymer resins of vinyl chloride - reference paste formulations (standard paste A/B) used for designation and comparison.