How long can high-strength nylon industrial yarn withstand at a temperature of 150℃? The data on thermal aging reveals the answer. 

high-strength nylon industrial yarns are widely used in various fields such as seat belts, sewing threads, fishing nets, cordage for car tires, and outdoor sunshades due to their excellent wear resistance, fatigue resistance and tensile strength. However, in high-temperature environments - such as the engine compartment of a car, industrial heat setting processes or outdoor use in tropical regions - the performance of nylon yarns will deteriorate over time. 150℃ is the "demarcation temperature" for many nylon application scenarios. Below, from the perspectives of thermal aging principles and data interpretation, we will help you understand how to evaluate and select more durable high-strength nylon industrial yarns. 

1. What happened to nylon at high temperatures? 

The polyamide (nylon) molecular chains will undergo irreversible degradation under the combined action of high temperature, oxygen and moisture, resulting in a decrease in strength, discoloration and brittleness. 

Thermal oxidative aging is the main cause: At a temperature of 150℃, the amide bonds in the molecular chains of nylon are prone to undergo oxidative breakage, resulting in a decrease in the degree of polymerization. This degradation is irreversible, and the higher the temperature and the longer the time, the faster the degradation rate. When the molecular chains break to a certain extent, the mechanical properties of the fiber will significantly decline. 

The aging process under humid and hot conditions is more complex: If the high-temperature environment is accompanied by moisture (such as in tropical regions or during the humid heat setting process), water molecules will accelerate the hydrolysis reaction of nylon, further weakening the molecular chains. Therefore, when evaluating the heat resistance of nylon, it is necessary to distinguish between the two conditions of "dry heat aging" and "wet heat aging". 

The function of anti-aging additives: By adding heat stabilizers such as copper salts or antioxidants, the thermal and oxidative aging process of nylon can be significantly delayed. When purchasing, inquire with the supplier whether anti-aging additives have been added and the corresponding heat resistance grade. This is a reference for evaluating its high-temperature applicability. 

II. How to Interpret and Utilize Heat Aging Data? 

During the procurement process, the supplier may provide data on the strength retention rate after high-temperature aging. Correctly interpreting these data can help in selecting the appropriate specifications. 

Focus on the strength retention rate curve: It is recommended to pay attention to the "strength retention rate - time curve" rather than just looking at a single point of data. For example, for the same specification of nylon filament at 150℃, the strength retention rate after 200 hours might be 80%, but it drops to 60% after 400 hours. The shape of this curve can help you determine the attenuation rate of the filament under high temperature. Shengjie Heuli Chemical Fiber Co., Ltd. in Changzhou has over 22 years of experience in the chemical fiber industry, and its products are widely used in sectors such as the automotive industry and the construction industry. 

Based on your actual usage period: According to the expected service life of your product, select the specification that can maintain sufficient strength within the corresponding time frame. If your product needs to be used continuously in a 150℃ environment for several hundred hours, you should choose the specification with better thermal aging performance. 

Consider the effect of high temperature on color: When using products with light or bright colors, it is also necessary to pay attention to the yellowing degree of nylon under high temperature. This is similar to heat aging and affects the appearance and acceptance of the final product. 

Summary and Selection Suggestions 

When purchasing high-strength nylon industrial yarn, it is recommended to assess its high-temperature suitability according to the following steps: 

Clearly specify temperature and time: Inform the supplier of your maximum operating temperature and duration to ensure the selection of an appropriate heat stabilizer system. 

Provide thermal aging data: Request the strength retention rate over time curve at the target temperature (either dry heat or wet heat), and assess whether the rate of attenuation is in line with your usage cycle. 

Pay attention to color changes: When dealing with light-colored products, simultaneously assess the degree of high-temperature yellowing. 

Changzhou Shengjie Heuli Chemical Fibers Co., Ltd. has over 22 years of experience in the chemical fiber industry. It specializes in high-strength polyester industrial yarn, high-strength nylon industrial yarn, high-strength polypropylene industrial yarn, polyester flame-retardant yarn, polypropylene flame-retardant yarn, polyester FDY yarn, and variable-width yarn, etc. Its products are widely used in the automotive, textile, construction, sports and other industries. Please feel free to request samples for testing and communicate specific requirements. 

Official website: http://www.sjfibre.com