Views: 0 Author: Site Editor Publish Time: 2025-08-05 Origin: Site
Engineering plastics and elastomers serve as the backbone of countless industries today, finding critical roles in products ranging from automotive connectors and electronic housings to footwear soles and industrial seals. These versatile materials have transformed countless sectors thanks to their impressive balance of strength, flexibility, and ease of processing. Yet one critical challenge still threatens their long-term durability: exposure to moisture and heat can trigger hydrolysis, silently degrading their molecular structure over time. As demand grows for products that perform reliably in humid, wet, or high-temperature environments, finding ways to improve hydrolysis resistance has become more important than ever. This article explores how advanced anti-hydrolysis agents can protect polymers, extend service life, and safeguard end-use performance.
Many modern engineering plastics and elastomers offer outstanding mechanical strength, flexibility, and design freedom. However, when exposed to moisture—especially in combination with heat—these materials can undergo a chemical reaction known as hydrolysis, which gradually breaks down their molecular structure.
Hydrolysis occurs when water molecules attack the ester or amide bonds within a polymer chain. Over time, this leads to chain scission, reducing molecular weight and severely compromising the material’s mechanical integrity. The consequences of hydrolysis degradation are significant: reduced tensile strength, lower impact resistance, increased brittleness, surface cracking, and ultimately, premature product failure.
As industries demand ever more reliable materials that can withstand harsh conditions—such as automotive components exposed to engine heat and humidity, or outdoor applications in tropical climates—the need to improve hydrolysis resistance in plastics and elastomers has never been more critical. Effective solutions not only protect material performance but also reduce costly maintenance, replacements, and warranty claims.
Several widely used engineering polymers are particularly susceptible to hydrolysis due to the presence of ester or amide bonds in their backbone structures. Here’s an overview of some key examples:
PET is a versatile thermoplastic found in fibers, bottles, films, and injection-molded parts. It offers excellent strength and dimensional stability. However, its ester linkages are vulnerable to hydrolytic attack, especially in applications involving hot water—such as dishwasher components or industrial filtration.
PBT is another polyester commonly used in automotive connectors, housings, and electronic components. It combines good electrical properties with mechanical strength, but under high humidity and elevated temperatures, its ester bonds can break down, leading to embrittlement.
Nylons are prized for their toughness, wear resistance, and ability to form precise gear teeth and bearings. However, their amide bonds can be cleaved by water, especially under heat. Hydrolysis in polyamides results in loss of molecular weight, reduced tensile strength, and dimensional instability.
Polyurethanes—both thermoplastic (TPU) and thermoset—are extensively used in footwear soles, hoses, foam cushions, and protective coatings. The ester segments in polyester-based PU make them prone to hydrolysis, which leads to softening, cracks, and diminished load-bearing ability.
Cast polyurethane elastomers are widely applied in wheels, seals, and dynamic industrial parts. Hydrolysis can cause these elastomers to lose elasticity, crack under stress, and fail prematurely when exposed to humid or wet environments.
An anti-hydrolysis agent, or hydrolysis stabilizer, is a specialized additive designed to protect polymers by interrupting the hydrolysis process. These compounds actively defend vulnerable ester or amide bonds in the polymer chain against moisture-induced degradation.
Anti-hydrolysis agents typically function by:
Reacting with carboxylic acid end groups formed when ester or amide bonds start breaking. This prevents further chain scission.
Scavenging water or neutralizing hydrolytic catalysts, thereby reducing the rate of hydrolysis.
Stabilizing the polymer’s molecular architecture, maintaining its mechanical and dimensional properties even under harsh conditions.
Polycarbodiimides: Highly effective for protecting polyesters and polyamides. They react with carboxylic acid end groups to form stable linkages, essentially “healing” the polymer.
Carbodiimide oligomers: Similar in function but lower in molecular weight, offering shorter-term protection.
Hindered amine light stabilizers (HALS): Primarily used for UV stabilization but can contribute to overall polymer durability, including against hydrolysis.
These chemistries are crucial tools to improve hydrolysis resistance, especially in demanding applications.
For polyesters like PET and PBT, hydrolysis involves water molecules attacking the ester bonds, resulting in chain breaks and the formation of carboxylic acids and alcohol groups. This lowers molecular weight and compromises mechanical strength.
Polycarbodiimide anti-hydrolysis agents react with the carboxylic acids formed during this process, effectively blocking further degradation. This extends the polymer’s lifetime under hot and humid conditions, making them ideal for automotive under-hood components, electrical connectors, and home appliance parts that may encounter steam or high temperatures.
Polyamides have amide linkages, which hydrolyze into carboxylic acids and amines under heat and moisture. This leads to reduced molecular weight, weakening gears, bearings, and industrial fasteners made from nylon.
Adding carbodiimides helps by reacting with the carboxylic acid end groups, preventing chain scission from progressing. As a result, polyamide fibers, monofilaments, and precision machine components maintain their strength and dimensional accuracy for much longer, even in humid industrial environments.
Polyester-based polyurethanes are notably sensitive to hydrolysis. As moisture attacks their ester bonds, the material softens, develops micro-cracks, and eventually loses load-bearing capacity. In footwear soles, this leads to crumbling or cracking, while in seals and rollers, it causes deformation and leaks.
Integrating anti-hydrolysis agents into PU formulations preserves mechanical properties such as hardness, rebound, and flexibility. This is critical for products exposed to tropical climates, water contact, or high-humidity processing lines.
Implementing the right anti-hydrolysis agents provides multiple clear benefits:
Longer product lifespan: Engineered plastics and elastomers retain their original mechanical properties, significantly reducing failures in humid or high-temperature environments.
Maintains key properties: Materials hold their tensile strength, elongation, impact resistance, and dimensional stability.
Minimized customer complaints and warranty costs: By reducing hydrolysis-driven failures, manufacturers build trust and brand reputation.
Lower maintenance and replacement expenses: Especially important for industrial machine parts, automotive connectors, and infrastructure applications.
These advantages demonstrate why investing in effective stabilizers to improve hydrolysis resistance is a smart strategy for manufacturers focused on quality and durability.
Anti-hydrolysis agents are typically incorporated by:
Direct addition during compounding: Blended with the polymer granules and other additives in an extruder.
During injection molding or extrusion: Ensures thorough dispersion in the molten polymer for maximum effectiveness.
Liquid, powder, or masterbatch forms are available to suit different manufacturing setups.
Effective dosage usually ranges from 0.5% to 2% by weight, depending on:
Polymer type and its inherent vulnerability.
The severity of the operating environment.
Performance and warranty requirements of the final product.
Manufacturers often conduct tests to determine the optimal loading that balances protection with cost.
Modern anti-hydrolysis agents are formulated to work seamlessly with:
Pigments and colorants, avoiding unwanted discoloration.
Fillers, reinforcements, and flame retardants, ensuring they maintain dispersion and effectiveness.
Other stabilizers, such as UV absorbers or antioxidants, to provide multi-functional protection.
To achieve the best results, thorough mixing and uniform dispersion are key. For specialized or heavily filled systems, small-scale trials help confirm compatibility and processing behavior.
In today’s demanding industrial and consumer environments, engineering plastics and elastomers like PET, PBT, PA, PU, and PU rubber constantly face moisture and temperature swings that accelerate hydrolysis. If left unaddressed, this leads to weakened mechanical properties, surface cracking, and costly product failures. Incorporating advanced anti-hydrolysis agents—particularly polycarbodiimide-based solutions—is a proven strategy to improve hydrolysis resistance, protecting polymer chains from moisture attack and significantly extending product life. By doing so, manufacturers can deliver more reliable, longer-lasting components, minimize warranty claims, and build a stronger reputation for quality and durability.
For businesses aiming to produce high-performance plastics and elastomers that withstand harsh, humid, or hot conditions, using the right hydrolysis stabilizers isn’t just beneficial—it’s essential. To explore how these advanced additives can transform your products and meet your specific formulation needs, consider reaching out to Suzhou Ke Sheng Tong New Materials Technology Co., Ltd.. As an experienced supplier specializing in anti-hydrolysis solutions, they can provide tailored recommendations and support to help you achieve superior long-term performance. Visit their website or contact their technical team today to learn more.
