{"title":"A novel polyhedral oligomeric silsesquioxane antioxidant based on amide-linked hindered phenols and its anti-oxidative behavior in polyamide 6,6","authors":"","doi":"10.1016/j.polymdegradstab.2024.110939","DOIUrl":null,"url":null,"abstract":"<div><p>A novel polyhedral oligomeric sesquisiloxane (POSS) antioxidant based on amide-linked hindered phenols (HPAm-POSS) was successfully synthesized via a nucleophilic substitution reaction. The chemical structure of HPAm-POSS was characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), MALDI-TOF mass spectrometry (MS), and thermogravimetric analysis (TGA). The antioxidative efficiency of HPAm-POSS in polyamide 6,6 (PA66) was investigated by accelerated thermal aging tests, processing experiments, and extraction experiments and compared with a commercial hindered phenol antioxidant, Irganox 1098, at an equivalent concentration of active hindered phenolic stabilizer groups. The results showed that the thermal-oxidative stability of PA66 materials was significantly improved by the incorporation of either HPAm-POSS or Irganox 1098. Although the antioxidant efficiency of HPAm-POSS in the long-term accelerated thermal aging of PA66 at 150 °C in an air oven is slightly lower than that of Irganox 1098, HPAm-POSS is slightly more effective than Irganox 1098 in inhibiting the degradation of PA66 during multiple processing. Notably, HPAm-POSS exhibited higher anti-extraction properties in PA66 due to its higher molecular weight and lower migration ratio. Consequently, PA66/0.35 %HPAm maintains thermo-oxidative stability even after being extracted with organic media such as ethanol, toluene, or ethylene glycol, whereas PA66/0.30 %1098 is highly susceptible to thermo-oxidative degradation due to the physical loss of Irganox 1098 by extraction.</p></div>","PeriodicalId":406,"journal":{"name":"Polymer Degradation and Stability","volume":null,"pages":null},"PeriodicalIF":6.3000,"publicationDate":"2024-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Polymer Degradation and Stability","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0141391024002830","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
A novel polyhedral oligomeric sesquisiloxane (POSS) antioxidant based on amide-linked hindered phenols (HPAm-POSS) was successfully synthesized via a nucleophilic substitution reaction. The chemical structure of HPAm-POSS was characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), MALDI-TOF mass spectrometry (MS), and thermogravimetric analysis (TGA). The antioxidative efficiency of HPAm-POSS in polyamide 6,6 (PA66) was investigated by accelerated thermal aging tests, processing experiments, and extraction experiments and compared with a commercial hindered phenol antioxidant, Irganox 1098, at an equivalent concentration of active hindered phenolic stabilizer groups. The results showed that the thermal-oxidative stability of PA66 materials was significantly improved by the incorporation of either HPAm-POSS or Irganox 1098. Although the antioxidant efficiency of HPAm-POSS in the long-term accelerated thermal aging of PA66 at 150 °C in an air oven is slightly lower than that of Irganox 1098, HPAm-POSS is slightly more effective than Irganox 1098 in inhibiting the degradation of PA66 during multiple processing. Notably, HPAm-POSS exhibited higher anti-extraction properties in PA66 due to its higher molecular weight and lower migration ratio. Consequently, PA66/0.35 %HPAm maintains thermo-oxidative stability even after being extracted with organic media such as ethanol, toluene, or ethylene glycol, whereas PA66/0.30 %1098 is highly susceptible to thermo-oxidative degradation due to the physical loss of Irganox 1098 by extraction.
期刊介绍：
Polymer Degradation and Stability deals with the degradation reactions and their control which are a major preoccupation of practitioners of the many and diverse aspects of modern polymer technology.
Deteriorative reactions occur during processing, when polymers are subjected to heat, oxygen and mechanical stress, and during the useful life of the materials when oxygen and sunlight are the most important degradative agencies. In more specialised applications, degradation may be induced by high energy radiation, ozone, atmospheric pollutants, mechanical stress, biological action, hydrolysis and many other influences. The mechanisms of these reactions and stabilisation processes must be understood if the technology and application of polymers are to continue to advance. The reporting of investigations of this kind is therefore a major function of this journal.
However there are also new developments in polymer technology in which degradation processes find positive applications. For example, photodegradable plastics are now available, the recycling of polymeric products will become increasingly important, degradation and combustion studies are involved in the definition of the fire hazards which are associated with polymeric materials and the microelectronics industry is vitally dependent upon polymer degradation in the manufacture of its circuitry. Polymer properties may also be improved by processes like curing and grafting, the chemistry of which can be closely related to that which causes physical deterioration in other circumstances.
京公网安备 11010802042870号
京ICP备2023020795号-1
分享
求助内容：
应助结果提醒方式：
扫码关注我们
