Water absorption in polymers directly impacts both product quality and production efficiency — under uncontrolled environmental conditions, materials such as nylon, PET, and polycarbonate — take in water that penetrates polymer chains. It doesn’t just cling externally — it infiltrates the polymer matrix, causing disruptions in the melt phase.

To achieve proper mixing, polymer pellets are subjected to elevated temperatures for fusion with fillers, stabilizers, and colorants}. Even trace amounts of humidity in the feedstock — it transforms into gaseous water under process conditions. This steam generation creates bubbles, voids, or entrapped gas pockets, manifesting as surface blemishes, poor shine, or inconsistent texture. They detract from visual quality, and significantly weaken structural integrity, compromising load-bearing capacity and resilience.

Beyond physical defects, moisture can induce chemical degradation. For materials like PET and nylon, water initiates chain scission, an irreversible process that shortens polymer backbone length. The molecular weight distribution shifts downward, and diminishes the material’s ability to flow uniformly. Lower molecular weight means the polymer becomes more brittle, compromising long-term structural reliability, potentially leading to field failures in high-performance parts.

Eliminating moisture before processing is a mandatory industry practice. Resins like nylon and PET require thermal treatment within this range, over several hours tailored to resin sensitivity and ambient moisture. Advanced lines employ closed-loop desiccant dryers or thermal dehumidifiers, achieving the industry-standard threshold for engineering plastics.

Dried material is vulnerable to rehydration during handling. Therefore, strict handling and storage protocols are essential. Operators must utilize airtight storage, dry-air purged feed systems, or vacuum-sealed bins. Additionally, operators must continuously monitor ambient humidity in the compounding area, A limited window—often under an hour—must be maintained between drying and processing.

It is a fundamental parameter that dictates product quality and process reliability. Neglecting moisture control leads to expensive scrap, rework, and downtime. It risks long-term customer relationships and compliance standards. By implementing rigorous drying, sealed handling, اکسیر پلیمر and environmental monitoring, they guarantee repeatable performance and defect-free parts.