改性剂对纳米片状羟基磷灰石/聚乳酸复合材料性能的影响

黄梽焕; 万怡灶; 朱享波; 张全超; 杨志伟; 罗红林

doi:10.13801/j.cnki.fhclxb.20201028.001

改性剂对纳米片状羟基磷灰石/聚乳酸复合材料性能的影响

doi: 10.13801/j.cnki.fhclxb.20201028.001

华东交通大学　先进材料研究院，南昌 330013

基金项目: 国家自然科学基金(51662009；31660264；32000947)

详细信息

通讯作者:
罗红林，博士，副教授，硕士生导师，研究方向为生物医用复合材料　 E-mail：hlluo@tju.edu.cn

中图分类号: TB332; TQ332
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出版历程
- 收稿日期: 2020-07-27
- 录用日期: 2020-10-23
- 网络出版日期: 2020-10-28
- 刊出日期: 2021-03-15

Effect of modifier on properties of nano-platelet hydroxyapatite/polylactic acid composites

Institute of Advanced Materials, East China Jiaotong University, Nanchang 330013, China

摘要

摘要: 分别采用硅烷偶联剂(SC)和硬脂酸(SA)对纳米层片状羟基磷灰石(LHAp)进行表面改性，并通过挤塑工艺制备未改性和两种改性纳米片状羟基磷灰石(np-HAp)增强聚乳酸(PLA) (np-HAp/PLA、SC-np-HAp/PLA和SA-np-HAp/PLA)复合材料。比较了三种复合材料的微观结构、力学性能、热稳定性、结晶性及润湿性。利用XRD、FTIR、XPS、SEM、TGA、DSC、力学性能测试和接触角测试对复合材料的理化性能进行表征。研究发现，np-HAp、SA-np-HAp与PLA界面处存在相分离，而SC-np-HA与PLA两相界面结合紧密；与np-HAp/PLA复合材料相比，SC-np-HAp/PLA复合材料的压缩屈服强度和拉伸强度分别提高了9.4%和6.6%，而SA-np-HAp/PLA复合材料的压缩屈服强度和拉伸强度则出现减小；此外，与np-HAp/PLA复合材料相比，SC-np-HAp/PLA和SA-np-HAp/PLA复合材料的初始分解温度分别提高了7.4%和5.6%，SC-np-HAp/PLA复合材料的结晶度提高了6.7%，SA-np-HAp/PLA复合材料的结晶度则减小了3.5%。水接触角测试结果表明，与np-HAp/PLA复合材料和SA-np-HAp/PLA复合材料相比，SC-np-HAp/PLA复合材料具有更为优异的亲水性。上述结果表明，经SC改性后的np-HAp具有与PLA基体更好的界面结合能力，为制备性能优异的骨植入复合材料提供借鉴。
- 纳米片状羟基磷灰石 /
- 表面改性 /
- 硅烷偶联剂 /
- 硬脂酸 /
- 聚乳酸 /
- 复合材料
Abstract: The surface modification of nano-lamellar hydroxyapatite (LHAp) was carried out with silane coupling agent (SC) and stearic acid (SA), separately. The unmodified and two modified nano-platelet hydroxyapatite (np-HAp) reinforced polylactic acid (PLA) (np-HAp/PLA, SC-np-HAp/PLA, and SA-np-HAp/PLA) composites were prepared by extrusion process. The microstructure, mechanical properties, thermal stability, crystallinity, and wettability of the three composites were compared. XRD, FTIR, XPS, SEM, TGA, DSC, mechanical property test, and contact angle test were conducted to characterize the physiochemical properties of the composites. The results show that there is phase separation at the interface of np-HAp or SA-np-HAp and PLA, and the interface of SC-np-HAp/PLA composite demonstrates strong interface adhesion. Compared with np-HAp/PLA composite, the compressive yield strength and tensile strength of SC-np-HAp/PLA composite increase by 9.4% and 6.6%, respectively, while SA-np-HAp/PLA composite exhibites reductions. Further, compared with np-HAp/PLA composite, the initial decomposition temperature of SC-np-HAp/PLA and SA-np-HAp/PLA composites increases by 7.4% and 5.6%, respectively, and crystallinity of the former increases by 6.7%, while the latter decreases by 3.5%. Compared with np-HAp/PLA and SA-np-HAp/PLA composites, the SC-np-HAp/PLA composite has a significantly lower water contact angle. These results indicate that the SC-modified np-HAp has better interface compatibility with PLA matrix, which will provide a new criterion for the preparation of high-performance bone implant composites.
- nano-platelet hydroxyapatite /
- surface modification /
- silane coupling agent /
- stearic acid /
- polylactic acid /
- composites

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图 1 纳米片状羟基磷灰石/聚乳酸(np-HAp/PLA)复合材料的制流程示意图

Figure 1. Schematic diagram of preparation of nano-platelet hydroxyapatite/polylactic acid (np-HAp/PLA) composites

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图 2 层片状羟基磷灰石(LHAp)、硬脂酸(SA)-np-HAp、硅烷偶联剂(SC)-np-HAp ((a),(b))及其复合材料(c)的XRD图谱；SC、SA、LHAp、SA-np-HAp和SC-np-HAp的FTIR图谱(d)；LHAp (e)、SA-np-HAp (f)和SC-np-HAp (g)的O1s高分辨XPS图谱；SA和SC与np-HAp的结合过程示意图(h)

Figure 2. XRD patterns of lamellar hydroxyapatite (LHAp), stearic acid (SA)-np-HAp, silane coupling agent (SC)-np-HAp ((a), (b)) and PLA compsites (c); FTIR spectra of SC, SA, LHAp, SA-np-HAp and SC-np-HAp (d); High resolution XPS O1s spectra of LHAp (e), SA-np-HAp (f) and SC-np-HAp (g); Schematic illustration showing interaction between SA/SC and np-HAp (h)

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图 3 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料的压缩(a)和拉伸(b)应力-应变曲线

Figure 3. Representative compression (a) and tensile (b) stress-strain curves of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites

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图 4 PLA、np-HAp/PLA、SA-np-HAp/PLA、SC-np-HAp/PLA复合材料拉伸断口的SEM图像

Figure 4. SEM images of tensile fracture of PLA, np-HAp/PLA, SA-np-HAp/PLA, SC-np-HAp/PLA composites

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图 5 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料的TGA (a)和DTG (b)曲线

Figure 5. TGA (a) and DTG (b) curves of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites

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图 6 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料的DSC曲线

Figure 6. DSC curves of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites

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图 7 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料表面的润湿性(p<0.05，n=6) (a)和表面润湿性示意图(b)

Figure 7. Water contact angles (a) and schematic diagram of wettability (b) of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites (p < 0.05, n=6 in each group)

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表 1 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料的力学性能

Table 1. Mechanical properties of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites

Material	Compressive yield strength/MPa	Compression modulus/MPa	Tensile strength/MPa	Young’s modulus/MPa
PLA	74.6 (4.6)	424.8 (12.2)	68.7 (1.2)	714.9 (21.4)
np-HAp/PLA	84.7 (3.4)	525.1 (38.9)	76.0 (1.6)	838.5 (16.2)
SA-np-HAp/PLA	76.0 (3.3)	576.6 (44.0)	72.1 (1.1)	797.8 (22.5)
SC-np-HAp/PLA	92.7 (1.4)	614.6 (27.6)	81.0 (0.8)	832.1 (12.9)
Note: Values in the parentheses represent the standard deviations of replicates.

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表 2 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料的热稳定性

Table 2. Thermal stability of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites

Material	PLA	np-HAp/PLA	SA-np-HAp/PLA	SC-np-Ap/PLA
T_onset/℃	353.3	364.0	384.6	391.0
T_50%/℃	395.6	415.6	420.0	426.7
R_m/%	0	5.3	6.0	8.9
Notes: T_onset—Initial decomposition temperature; T_50%—Unstable state temperature; R_m—Residual mass at 600℃.

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表 3 PLA、np-HAp/PLA、SA-np-HAp/PLA和SC-np-HAp/PLA复合材料在加热和冷却过程中的DSC热参数

Table 3. Thermal parameters of PLA, np-HAp/PLA, SA-np-HAp/PLA and SC-np-HAp/PLA composites in DSC analysis during heating and cooling

Material	T_g/℃	T_cc/℃	ΔH_cc/(J·g^–1)	T_m/℃	ΔH_m/(J·g^–1)	χ_c/%
PLA	60.2	110.2	33.2	169.3	14.7	21.9
np-HAp/PLA	60.5	96.4	9.55	168.1	41.1	37.4
SA-np-HAp/PLA	60.0	99.2	13.6	167.5	42.2	33.9
SC-np-HAp/PLA	60.0	—	—	167.1	37.2	44.1
Notes: T_g—Glass transition temperature; T_cc—Cold crystallization temperature; ΔH_cc—Cold crystallization enthalpy; T_m—Melting temperature; ΔH_m—Melting enthalpy; χ_c—Crystallinity.

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