摘要
随着增材制造技术的不断进步,3D打印原材料的热性能和动态热机械性能标准化研究受到关注。为了快速评估这些性能,本文采用固体分析仪,探讨直接测试聚乳酸(PLA)3D打印线材热性能和动态热机械性能的方法。相比于传统的多设备、多次测量,此方法减少了系统误差,保证了结果的一致性与可靠性。通过测试PLA样品储能模量与应变的关系,验证了在测试温度范围内PLA样品的临界应变小于0.3%,确保测试能在线性黏弹区内完成。通过与差示扫描量热仪的数据比对,证明此方法能同步获得材料玻璃化转变温度、结晶温度及熔融温度,并可解析材料黏弹性对温度的依赖关系。进一步分析不同升温速率对材料玻璃化转变温度、结晶温度和熔融温度的影响,发现当升温速率从3℃/min增加至10℃/min, PLA玻璃化转变温度降低约1.5℃,结晶和熔融区间内的模量平台区缩短,表明升温速率对PLA链段的松弛和伸展程度略有影响,但对PLA的熔融结晶过程有显著影响。通过平行样品的重复测试,证明此方法具有较好的精密度,进一步通过格拉布斯检验,证明方法具有稳定性。本研究可为后续材料热性能和动态热机械性能研究提供参考。
With the continuous advancements of additive manufacturing technology,the standardization researches on the thermal properties and dynamic thermomechanical properties of 3D printed raw materials have received much attentions.To quickly evaluate these properties,this study employed a solid-state analyzer to explore a direct method for testing the thermal and dynamic thermomechanical characteristics of 3D printed polylactic acid(PLA) filaments.Compared to the traditional multi-device and multi-measurement approaches,this method minimized systematic errors,ensuring the result consistency and reliability.Through testing the relationships between storage modulus and strain of PLA samples,the results show that the critical strain of PLA samples is less than 0.3%in the testing temperature range,which ensures that the tests could be done in the linear viscoelastic region.By comparing with the data from differential scanning calorimetry,this approach could simultaneously determine the material glass transition temperature,crystallization temperature,and melting temperature.This approach could also offer detailed insights into the temperature dependence of the material viscoelasticity.Further analysis of the effects of different heating rates on the glass transition temperature,crystallization temperature,and melting temperature of materials reveals that,when the heating rate increases from 3 ℃/min to 10 ℃/min,the glass transition temperature of PLA decreases by approximately 1.5 ℃,and the modulus plateau region in the crystallization and melting ranges shortens.The heating rate has a slight effect on the relaxation and stretching of PLA chains,but has a significant impact on the melting crystallization process of PLA.Through the repeated tests of parallel samples,the results show that this method exhibits good precision,and the Grubb's test further validates its stability.The researches could provide references for subsequent studies on the thermal properties and dynamic thermomechanical properties of materials.
作者
韦莉
WEI Li(Center for Advanced Low-dimension Materials,Donghua University,Shanghai 201620,China)
出处
《塑料工业》
CAS
CSCD
北大核心
2024年第9期99-103,共5页
China Plastics Industry
关键词
动态热机械性能
热性能
聚乳酸
固体分析仪
Dynamic Thermomechanical Property
Thermal Property
Polylactic Acid
Solid Analysis Instrument
