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Bilal Demirel Nihat B. İnaner Derya U. Gezer Fugen Daver Ali Yaras Fatih Akkurt 《Polymer Engineering and Science》2021,61(7):2043-2054
Polyethylene terephthalate (PET)/nano-hydroxyapatite (nHAp) composite granules were obtained using twin-screw extruder. Preforms were prepared by injection molding and then PET/nHAp bottles were produced by blow molding. For PET bottles with nHAp, the migration amounts of carboxylic acid (COOH), acetaldehyde (AA), diethylene glycol (DEG), and isophthalic acid (IPA); glass transition temperature (Tg); melting temperature (Tm); and the maximum crystallization temperature (Tcry) were measured. The load-carrying capacity, burst strength, stress cracking, and regional material distribution tests were carried out on the bottles. X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and ultraviolet transmittance analyses were conducted to explain the changes in mechanical, chemical, physical properties, and light transmission of bottles. It was found out that the COOH amount increased and the AA content decreased with increasing nHAp amount. On the other hand, no change was observed in the amounts of DEG and IPA. Although the mechanical properties such as load-carrying capacity and burst strength of the bottles have improved, it has been determined that the standard environmental stress crack resistance test procedure cannot be applied to such a composite. Experimental findings indicate that nHAp disrupts the chemical structure of PET and it isolates harmful chemicals such as AA by forming intermolecular bonds. Moreover, with the addition of up to 0.8% nHAp, PET bottles block the light transmission approximately 80% within 400–700 nm wave length zone. The study demonstrates that the PET/nHAp composite bottles can be used in the food industry, particularly in the packaging of milk and milk products which are vulnerable to light exposure. 相似文献
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《中国矿业大学学报》2012,25(2)
用水热法合成的棒状纳米羟基磷灰石(nHA),引发ε-己内酯(ε-CL)开环聚合得到nHA-PCL复合材料。用静电纺丝法分别制备了聚己内酯(PCL)、nHA/PCL共混材料和nHA-PCL复合材料的3种电纺纤维膜。通过FT-IR、DSC、SEM、TGA和拉伸试验机表征了样品的结构、热性能和力学性能。结果表明:nHA-PCL电纺膜的结晶性能优于nHA/PCL材料,且热稳定性和力学性能都优于其他两种膜,nHA-PCL电纺膜的完全分解温度为420°C,拉伸强度和断裂伸长率分别达到28.2MPa和55.6%。3种膜的纤维直径均小于500 nm,nHA-PCL电纺膜的纤维表面比较粗糙。在人体仿生液中诱导矿化4 d后,nHA-PCL电纺膜纤维表面出现磷灰石沉积,而纯PCL和共混nHA/PCL电纺膜的纤维表面沉积的磷灰石很少,nHA-PCL复合电纺膜具有较好的诱导成骨性能。 相似文献
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以Na3PO4·12H2O,Ca(NO3)2·4H2O为前驱体,通过调节pH值控制PO43-的生成,利用微波液相法合成针状纳米羟基磷灰石(n-HA),采用X射线衍射(XRD)仪、拉曼光谱(RS)、红外光谱(FT-IR)、透射电镜(TEM)等对粉体相组成和形貌进行分析。结果表明,微波液相法可以快速合成类骨n-HA晶体,合成的n-HA晶体呈针状,尺寸在(10~20)nm×(50~70)nm之间,随着微波加热时间的延长,n-HA晶体的结晶程度升高,晶体形貌从针状向短柱状转变。 相似文献
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以表面活性剂磷酸酯为模板剂制备了具有层状结构的纳米羟基磷灰石(nano-hydroxyapatite,n-HA),该层状结构呈规则的周期性排列,层间距约为3.5 nm.用透射电子显微镜、广角X射线衍射、小角X射线衍射和Fourier变换红外光谱对材料的相组成、微观结构和形貌进行分析和表征.研究了液相体系中表面活性剂的浓度及反应温度对n-HA结构和形貌的影响.结果表明:反应温度和表面活性剂的浓度会显著影响材料的结构,最佳合成条件下可以形成相对均一的层状长条形n-HA. 相似文献
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选用湿态纳米羟基磷灰石(HA)与脂肪族聚氨酯(PU)为原料,采用溶液共混法和溶剂挥发法制备了亲水性羟基磷灰石/聚氨酯(HA/PU)纳米复合材料,并采用SEM、吸水实验和力学实验等方法对该复合材料的形貌和性能进行了研究。结果表明磷灰石晶体以纳米状态均匀地分布在PU基质中,过高含量的纳米HA易使纳米粒子团聚,不利于其在PU基体中的均匀分散;在制备PU的多元醇原料中引入亲水性较强的聚乙二醇,可提高PU表面和整体的亲水性;随着硬段含量的增加,复合材料的拉伸强度和弹性模量呈上升趋势,断裂伸长率下降;随着软段中聚乙二醇含量的升高,弹性模量大幅下降,拉伸强度和断裂伸长率先升高后下降;纳米HA的添加可同时提高复合材料的拉伸强度和断裂伸长率,当纳米HA的质量分数为30%时,复合材料的综合力学性能达到最佳。 相似文献
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应用示差扫描量热计(DSC)研究了用低分子量聚乳酸(PDLLA)接枝与未接枝两种处理的纳米羟基磷灰石(n-HA)对聚乙丙交酯(PLGA)等温结晶行为及熔融行为的影响,采用Avrami方程处理其等温结晶过程,计算结晶动力学参数;同时用配带热台的偏光显微镜(POM)研究了其结晶的晶核形态。结果表明该体系等温结晶行为可以用Avrami方程来描述;加入n-HA的两种复合材料及PLGA其结晶最快的温度都是110℃,且都是随着结晶温度的提高结晶速率变慢,但接枝的n-HA对提高PLGA基体的结晶速率、熔点及结晶活化能都比未接枝处理的要小。偏光显微镜研究得出加入n-HA的两种复合材料及PL-GA其球径形态相似,且都随温度升高而使结晶速度降低,但加入未接枝的n-HA比接枝后的结晶更快。以上结果说明接枝处理后的n-HA提高了两相界面结合,因而n-HA的异相成核能力比未接枝处理的要差。 相似文献
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以4 , 4′-亚甲基二环己基二异氰酸酯( H12MDI) 、聚乙二醇、蓖麻油、1 , 4-丁二醇和具有生物活性的纳米羟基磷灰石(n-HA) 为原料, 采用预聚法制备了纳米羟基磷灰石/ 聚氨酯( HA/PU) 复合材料, 并对其力学性能和热性能进行了研究。结果表明: 复合材料的拉伸强度和断裂伸长率随n-HA 含量的增加而提高。当n-HA 的质量百分数为30 %时, 复合材料的综合力学性能达到最佳, 与纯PU 相比, 拉伸强度和断裂伸长率分别提高了186 %和107 %。动态力学分析得出复合材料的储能模量随n-HA 质量百分含量的增加而显著上升。TGA 试验表明HA/PU 纳米复合材料的热稳定性能随n2 HA 的添加得到改善, 而DSC 分析显示n-HA 的加入在一定程度上降低了PU 软段的结晶度。这些结果均表明该n-HA/PU 是一种有应用前景的组织工程材料。 相似文献