【摘要】：熱塑性彈性體在常溫下具有橡膠彈性,在高溫下可塑化,兼具塑料的流動(dòng)性、可加工性和橡膠的彈性,廣泛應(yīng)用于醫(yī)療、電子配件、建筑、汽車行業(yè)、食品包裝等眾多領(lǐng)域。作為一種新型熱塑性彈性體,聚酰胺系熱塑性彈性體與聚氨酯和聚醚酯熱塑性彈性體類似,都屬于分段型嵌段聚合物,具有很好的應(yīng)用前景。本文采用兩步法(兩個(gè)階段)合成了具有分段型嵌段共聚物結(jié)構(gòu)的聚酰胺6熱塑性彈性體。第一階段先合成具有雙端羧基封端的預(yù)聚物聚酰胺6,第二階段再與聚乙二醇(PEG)進(jìn)行聚酯化反應(yīng)生成聚酰胺6熱塑性彈性體。研究了封端劑加入的時(shí)間、含量等對預(yù)聚物分子量的影響,優(yōu)化了時(shí)間、溫度、真空度、催化劑等合成工藝條件和參數(shù)。應(yīng)用傅里葉紅外光譜、氫譜核磁共振、熱重分析儀、差示掃描量熱儀、X射線衍射儀和掃描電鏡表征了預(yù)聚物和聚酰胺6型熱塑性彈性體的結(jié)構(gòu)與性能。研究結(jié)果表明:1、預(yù)聚物的優(yōu)化合成工藝為:240℃左右開環(huán)聚合4 h,加入封端劑1 h,抽真空1 h(真空度為0.05-0.07 MPa),嵌段共聚物合成的工藝條件:在溫度為250℃反應(yīng)下反應(yīng)3 h,抽真空1 h(真空度0.05-0.07 MPa);2、傅里葉紅外譜(FTIR)圖中出現(xiàn)了醇類的亞甲基團(tuán)的峰值,氫譜(1H-NMR)圖中合成的產(chǎn)物具有聚酰胺6和聚乙二醇兩者的峰值,表明嵌段共聚物合成成功;3、熱重分析和差示掃描量熱儀(DSC)測試說明共聚物在300℃以內(nèi)具有良好的熱穩(wěn)定性,在-50~192℃的區(qū)間顯示出良好的彈性性能,具有較寬的使用溫度范圍;4、XRD測試表明,軟段的加入使一部分的α晶型轉(zhuǎn)變成了γ晶型;5、SEM的測試表明軟段使聚酰胺6熱塑性彈性體具備橡膠彈性,但軟硬段存在一定的不相容性。
[Abstract]:Thermoplastic elastomer has rubber elasticity at room temperature, plasticizing at high temperature, plastic fluidity, processability and rubber elasticity. It is widely used in many fields such as medical treatment, electronic accessories, construction, automobile industry, food packaging and so on. As a new thermoplastic elastomer, polyamide thermoplastic elastomer is similar to polyurethane and polyether ester thermoplastic elastomer. Polyamide 6 thermoplastic elastomer with segmented block copolymer structure was synthesized by two step method. In the first stage, the prepolymer polyamide 6 with double end carboxyl group was synthesized, and then the polyamide 6 thermoplastic elastomer was synthesized by polyesterification with polyethylene glycol (PEG) in the second stage. The effects of the time and content of the entrapment on the molecular weight of the prepolymer were studied, and the synthesis conditions and parameters such as time, temperature, vacuum degree, catalyst and so on were optimized. The structure and properties of the prepolymer and polyamide 6 thermoplastic elastomer were characterized by Fourier transform infrared spectroscopy, hydrogen NMR, thermogravimetric analyzer, differential scanning calorimetry, X-ray diffraction and scanning electron microscope. The results show that: 1. The optimum synthesis process of prepolymer is as follows: about 240 鈩，

本文編號：2398386