Various Applications of Polyvinyl Alcohol Solubility Attributes

PVA’s solubility depends on hydrolysis degree, molecular weight, and temperature. Fully hydrolyzed PVA (DH ≥98%) requires temperatures above 80°C for dissolution, forming transparent solutions with high viscosity. Partially hydrolyzed grades (DH 87-89%) dissolve in cold water, ideal for instant-use applications. Low-molecular-weight PVA dissolves faster than high-MW variants due to reduced chain entanglement. Particle size affects dissolution rate: fine powders (≤100 mesh) dissolve in 15-30 minutes, while coarse granules may take 1-2 hours. Solubility peaks at 60-90°C, with modern formulations achieving complete dissolution in ≤20 minutes. Overheating (≥100°C) can cause gelation, while adding salts or alcohols may decrease solubility. For example, PVA 1799 (high DH, high MW) dissolves at 95°C, forming viscous solutions for film casting, whereas PVA 0888 (low DH, low MW) dissolves at 25°C for quick-apply adhesives.