化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2014年
11期
4620-4626
,共7页
泡沫%紫外老化%力学性能%色谱%氧化%降解
泡沫%紫外老化%力學性能%色譜%氧化%降解
포말%자외노화%역학성능%색보%양화%강해
foam%ultraviolet aging%mechanical properties%chromatography%oxidation%degradation
采用紫外加速老化方法,研究聚苯乙烯泡沫(EPS)在受到紫外老化后其外观和缓冲性能的变化规律,分析材料内部结构的变化。结果表明,随着加速紫外老化时间的延长,EPS分子链上产生某种显色基团,导致试样表面颜色变黄,EPS的最小缓冲系数值增大,缓冲效率降低;且随老化时间的增加,EPS分子量降低,分子量分布由2.13增大到3.76;分子结构中C元素含量减少,O元素含量逐渐增加,紫外线照射导致EPS表面受到激发并在水和热的共同作用下发生表面氧化,生成C O键、C-OH键等新的官能团;加速老化使EPS结构中大分子断链,化学键重组,导致力学性能下降。研究 EPS 材料的老化行为是推断其使用寿命和环境的基本依据,为EPS衬垫在运输包装过程中的合理应用提供参考依据。
採用紫外加速老化方法,研究聚苯乙烯泡沫(EPS)在受到紫外老化後其外觀和緩遲性能的變化規律,分析材料內部結構的變化。結果錶明,隨著加速紫外老化時間的延長,EPS分子鏈上產生某種顯色基糰,導緻試樣錶麵顏色變黃,EPS的最小緩遲繫數值增大,緩遲效率降低;且隨老化時間的增加,EPS分子量降低,分子量分佈由2.13增大到3.76;分子結構中C元素含量減少,O元素含量逐漸增加,紫外線照射導緻EPS錶麵受到激髮併在水和熱的共同作用下髮生錶麵氧化,生成C O鍵、C-OH鍵等新的官能糰;加速老化使EPS結構中大分子斷鏈,化學鍵重組,導緻力學性能下降。研究 EPS 材料的老化行為是推斷其使用壽命和環境的基本依據,為EPS襯墊在運輸包裝過程中的閤理應用提供參攷依據。
채용자외가속노화방법,연구취분을희포말(EPS)재수도자외노화후기외관화완충성능적변화규률,분석재료내부결구적변화。결과표명,수착가속자외노화시간적연장,EPS분자련상산생모충현색기단,도치시양표면안색변황,EPS적최소완충계수치증대,완충효솔강저;차수노화시간적증가,EPS분자량강저,분자량분포유2.13증대도3.76;분자결구중C원소함량감소,O원소함량축점증가,자외선조사도치EPS표면수도격발병재수화열적공동작용하발생표면양화,생성C O건、C-OH건등신적관능단;가속노화사EPS결구중대분자단련,화학건중조,도치역학성능하강。연구 EPS 재료적노화행위시추단기사용수명화배경적기본의거,위EPS츤점재운수포장과정중적합리응용제공삼고의거。
The variation of external appearance and cushioning properties of expanded polystyrene (EPS) was investigated and the change in internal structure of EPS was analyzed by using the ultraviolet (UV) accelerated aging method. The physical properties and chemical structure of EPS before and after aging were determined by colorimetric analysis, mechanical properties test, gel permeation chromatography (GPC), X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR/FTIR). With increasing time of UV accelerated aging, on the molecular chain of EPS some coloring groups that turned the color of the sample surface yellow were produced. With increasing aging time, minimum cushioning coefficient value increased, and cushioning efficiency decreased. When aging time was more than 100 h, growth rate of cushioning coefficient had a significant rise, and there was a tendency to lose cushioning property. With increasing aging time, molecular weight of EPS decreased, and molecular weight distribution increased from 2.13 to 3.76, indicating photo-oxidative degradation. So stability of molecular structure of EPS was destroyed. C element content decreased and O element content increased gradually in molecular structure of EPS. UV irradiation excited EPS surface, and oxidation occurred under the interaction of water and temperature to generate new functional groups, such as CO, C-OH bonds. Accelerated aging broke macromolecular chain to reorganize chemical bond in EPS structure, resulting in the decline of mechanical properties. The aging behavior of EPS is the fundamental basis to determine service life and service environment. It provides a reference for the reasonable application of EPS liner in transport packaging processes.