新型功能化蒙脱土对SEBS的性能影响及其协同膨胀阻燃研究

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摘要

聚苯乙烯-聚乙烯/丁烯-聚苯乙烯三嵌段共聚物(SEBS)是一种典型的热塑性弹

性体，具有良好的弹性和可反复成型加工的优点，有着广泛的应用前景。SEBS 的

硬段与软段易缠结，常需进行充油处理以提高在成型加工时的流动性。然而，操

作油的加入会致使 SEBS 热稳定性和力学性能下降，且极易燃烧，存在火灾隐患。

提高 SEBS 及其共混材料的力学性能以及阻燃性能已成为其应用领域的研究热点。

本论文采用我国丰产的蒙脱土，结合热稳定优良的有机插层剂，并利用其片层的

纳米效应，制备了 SEBS/蒙脱土纳米复合材料。

本文首先采用热稳定性高且具有阻燃效应的有机磷盐对蒙脱土进行有机插层

处理，以克服常规的有机铵盐改性的蒙脱土热稳定性不高，并进一步导致聚合物

材料热稳定性下降的缺点。在有机磷盐对蒙脱土进行有机插层的基础上，采用不

同硅烷偶联剂对其进行再次改性，此外还探索了采用磷酸酯胶束插层改性蒙脱土

的方法。本论文使用傅立叶红外光谱仪(FTIR)、X射线光电子能谱(XPS)、X射线

衍射仪(XRD)、热重分析仪(TG)和扫描电子显微镜(SEM)对功能化蒙脱土的层间结

构、形貌和热稳定性进行测量和表征。通过 XRD、透射电子显微镜（TEM）、 SEM、

TG 和万能材料试验机等对采用熔融共混的方式制备的 SEBS/功能化蒙脱土纳米复

合材料的结构、形貌、热性能和力学性能进行了系统的研究和分析。

研究表明，经过有机磷盐插层后的蒙脱土片层间距明显增加，而硅烷偶联剂

的类型对有机磷盐插层蒙脱土的层间距、表面形貌影响显著。受到硅烷偶联剂极

性，链长的影响，硅烷再接枝功能化蒙脱土在与 SEBS 熔融复合时，SEBS 分子链

更容易插层进入短链硅烷再接枝的蒙脱土的片层中。短链硅烷改性功能化蒙脱土

表面的 Si-O 网状结构还可以延缓热量传递，保持了有机磷盐插层改性蒙脱土对

SEBS 热稳定性的提升作用；而长烷链硅烷(十六烷基三甲氧基硅烷)容易与 SEBS

分子链之间形成一定的缠结，能够有效地传递拉伸应力，从而在保证 SEBS 橡胶弹

性的同时，起到了明显的增强作用，当长烷链硅烷再接枝功能化蒙脱土添加量为 1

phr 时，复合材料的模量、强度和断裂伸长率分别增加了 24%，65%和4%。

SEBS 极易燃烧且难以阻燃，为了提高 SEBS 膨胀阻燃体系的阻燃效率，本论

文提出了采用蒙脱土与膨胀阻燃剂协效阻燃的方案。但常规的有机铵盐改性的蒙

脱土会促进 SEBS 的提前分解，对 SEBS 膨胀阻燃体系的氧指数（LOI）无明显提

升，协效阻燃效果不明显。为了提高 SEBS 膨胀阻燃体系的阻燃效率，本文采用氨

基硅烷功能化改性蒙脱土(K-H-OMMT)对SEBS 膨胀阻燃体系进行协效阻燃。当添

加2 phr 的K-H-OMMT 时，SEBS 膨胀阻燃体系(膨胀阻燃剂的含量为 30 phr )的

LOI 由24.3%提高至 26.5%，由于 K-H-OMMT 表面的氨基基团可以参与膨胀阻燃

剂炭层的快速形成，阻燃协效作用明显。K-H-OMMT 的加入还能够减小膨胀阻燃

剂分散相尺寸，提高共混物的相容性，提高了 SEBS 膨胀阻燃体系的拉伸强度和模

量。

本文还进一步探索了双酚 A 双磷酸二苯酯(BDP)胶束插层功能化蒙脱土对

SEBS 膨胀阻燃体系的影响，少量 BDP 胶束插层功能化蒙脱土可以提高 SEBS 膨

胀阻燃体系的 LOI，这是由于 BDP 形成的磷酸酯液膜覆盖在炭层表面，阻隔了可

燃气体和热量的传递。少量 BDP 胶束插层功能化蒙脱土的加入还使得 SEBS 膨胀

阻燃复合材料的拉伸模量、强度和断裂伸长率分别增加 9%、36%和28%，起到了

增强和增柔的双重效果。

关键字：有机磷盐硅烷偶联剂功能化蒙脱土 SEBS 膨胀阻燃

ABSTRACT

Polystyrene-b-(ethylene-co-butylene)-b-styrene block copolymer (SEBS) is a

widely used thermoplastic elastomer (TPEs) in different fields for good elasticity and

processability. There is a strong entanglement effect between the hard segments (PS)

and soft segments (PB) of SEBS chains, processing oil is often used to lower the

hardness and improve the processability, which may decrease the thermal stability and

mechanical performance of the blends, while increase the flammability. Improving the

mechanical and flame retardant behaviour of SEBS and their blends is a major

challenge for extending their applications.

Montmorillonite (MMT) is a 2:1 type layered silicate clay, the unit structure of

which comprises an alumina layer sandwiched between two silica layers. With increased

layer spacing and better affinity with polymer, nanocomposites of polymer and OMMT

are widely investigated in recent years for their significantly enhanced physical

properties. However, due to the quaternary ammonium salt degradation at high

temperatures and the negative catalysis effect on the degradation of nanocomposites for

the Hofmann elimination effect the thermal instability of the organoclay becomes a

strong limitation in melting processing of nanocomposites.

In this thesis, phosphorus-containing intercalating agents were selceted as organic

modifier for the MMT to get bigger interlayer space with enhanced thermal stability and

flame retardancy. And then different silane coupling agents were applied surface

treatment on the foregoing montmorillonite, for strengthing the interaction between the

MMT and SEBS matrix. In addition, functional montmorillonite prepared by

organophosphate micelle intercalating were explored. Fourier transform infrared

spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD),

thermogravimetric analyzer (TG) and scanning electron microscope (SEM) were used to

characterize the layer structure, morphology and thermal stability of the functional

montmorillonite.

SEBS and functional montmorillonite nanocomposites were prepared by melt

blending method. XRD, transmission electron microscope (TEM), SEM, TG and

universal material testing machine were used to characterize the structure, morphology,

thermal properties and mechanical properties of SEBS/montmorillonite composite

material.

The layers spacing of montmorillonite increased significantly after the phosphorus

salt modification. The types of silane coupling agent had a remarkable effect on layer

spacing and surface morphologies of the intercalated montmorillonite. Depend on the

polarity and length of silane coupling agent, SEBS molecular chain could easier

intercalate into the layers of short chain silane grafted montmorillonite than long-chain

silane grafted montmorillonite. Moreover，short chain silane grafted montmorillonite

could form the Si-O mesh structure on the surface of MMT, that could delay the heat

transfer, it can keep the thermal stability promotion of organic phosphorus salt

intercalating modified montmorillonite on the SEBS. Long chain silane could entangle

with SEBS molecular chain easily, which could deliver tensile stress effectively, that

could enhance the strength and toughness of SEBS. While adding 1wt%, the modulus,

strength and elongation at break of the nanocomposite increased by 24%, 65% and 4%,

respectively, it could achieve the dual effect of strengthening and toughening.

SEBS is flammable, in order to improve the flame retardant efficiency of

intumescent flame retarded SEBS, our research group has proposed the scheme of

adding montmorillonite into intumescent flame retardant (IFR). However, the

conventional organic ammonium salt modified montmorillonite would accelerate the

decomposition of SEBS, and has no obvious effect on enhancing the limited oxygen

index (LOI) of SEBS flame retardant system. In this paper, amino silane grafted

montmorillonite(K-H-OMMT) was prpepared to increase the flame retardant

performance of SEBS/IFR system. By adding 2 phr K-H-OMMT, the LOI index of

SEBS/IFR-30 increased from 24.3% to 26.5%, and the thermal stability improved

significantly whether under the N2 or O2 atmosphere. Because the amino groups on the

surface of the K-H-OMMT could promopt the forming of the char layer, obvious flame

retardant synergy effect can be realized. In addition, the tensile strength and modulus of

SEBS/IFR system were improved by adding a little amount of K-H-OMMT, for the

reduced dispersion size of the IFR and the improved compatibility with the SEBS

matrix.

This paper further explores the influence organophosphate micelle intercalated

montmorillonite (H-BDP-OMMT) on the SEBS/IFR system. The LOI index increased

by adding a small amount of H-BDP-OMMT. This may due to the phosphate ester

liquid membrane covering the surface of the forming char, which can be a block for the

transfer of the combustible gas and the heat. However, the organophosphate can inhibit

the char forming process; its flame retardant synergy effect on the IFR need to be

improved. While the tensile modulus, tensile strength and elongation at break

performance of SEBS/IFR increased by 9%, 36% and 28%, respectively,

H-BDP-OMMT played a dual effect of strengthening and toughening on the above

system.

Key Word ：Organic Phosphorus Salt, Silane Coupling Agent,

Functional Montmorillonite, SEBS, Intumescent Flame Retardant

中文摘要

ABSTRACT

第一章绪论 ............................................................................................................................... 1

1.1 蒙脱土及其有机功能化处理 ............................................................................................. 1

1.1.1 蒙脱土的结构特点 ...................................................................................................... 1

1.1.2 蒙脱土的有机功能化处理 .......................................................................................... 1

1.2 聚合物/蒙脱土纳米复合材料 ........................................................................................... 3

1.2.1 聚合物/蒙脱土纳米复合材料 .................................................................................... 3

1.2.2 SEBS 热塑性弹性体 ..................................................................................................... 4

1.2.3 SEBS 纳米复合材料及研究现状 ................................................................................. 5

1.3 聚合物/蒙脱土纳米阻燃 ................................................................................................... 7

1.3.1 聚合物的燃烧与阻燃机理 .......................................................................................... 7

1.3.2 蒙脱土在聚合物阻燃体系中的作用及研究现状 ...................................................... 8

1.4 研究意义、研究内容及创新点 ........................................................................................ 9

第二章实验部分 ....................................................................................................................... 11

2.1 实验材料及仪器设备 ....................................................................................................... 11

2.1.1 实验材料 ................................................................................................................... 11

2.1.2 实验仪器 ................................................................................................................... 11

2.2 实验步骤 .......................................................................................................................... 12

2.2.1 有机磷盐插层蒙脱土的制备 .................................................................................... 12

2.2.2 硅烷再接枝功能化蒙脱土的制备 ........................................................................... 12

2.2.3 胶束插层有机功能化蒙脱土的制备 ........................................................................ 12

2.2.4 SEBS/功能化蒙脱土纳米复合材料的制备 ............................................................... 12

2.2.5 SEBS/功能化蒙脱土纳米膨胀阻燃复合材料的制备 ............................................... 13

2.3 分析测试 .......................................................................................................................... 14

2.3.1 有机功能化蒙脱土的结构、形貌和性能 ............................................................... 14

2.3.2 SEBS/蒙脱土纳米复合材料结构及性能 ................................................................... 15

2.3.3 SEBS/蒙脱土纳米膨胀阻燃体系性能测试 ............................................................... 16

第三章功能化蒙脱土的结构与性能 ....................................................................................... 17

3.1 蒙脱土的有机功能化处理 ............................................................................................... 17

3.1.1 有机磷盐插层改性 .................................................................................................... 17

3.1.2 硅烷再接枝处理 ........................................................................................................ 18

3.1.3 胶束插层改性 ............................................................................................................ 19

3.2 功能化蒙脱土的结构与形貌 ........................................................................................... 19

3.3 功能化蒙脱土的热稳定性 ............................................................................................... 23

3.4 小结 ................................................................................................................................... 25

第四章 SEBS/功能化蒙脱土纳米复合材料 .............................................................................. 26

4.1 复合材料结构形貌 ........................................................................................................... 26

4.2 透明度与接触角 ............................................................................................................... 29

4.3 复合材料热稳定性能 ....................................................................................................... 31

4.3.1 不同功能化蒙脱土对 SEBS 的影响 .......................................................................... 31

4.3.2 短链硅烷再接枝功能化蒙脱土含量对 SEBS 的影响 ............................................. 32

4.4 复合材料力学性能 ........................................................................................................... 34

4.4.1 不同功能化蒙脱土对 SEBS 的影响 .......................................................................... 34

4.4.2 长链硅烷再接枝功能化蒙脱土含量对 SEBS 的影响 .............................................. 36

4.5 小结 ................................................................................................................................... 37

第五章硅烷再接枝功能化蒙脱土协同 SEBS 膨胀阻燃 ......................................................... 38

5.1 阻燃性能 ........................................................................................................................... 38

5.1.1 氧指数 ........................................................................................................................ 38

5.1.2 炭层形貌 .................................................................................................................... 39

5.2 热稳定性 ........................................................................................................................... 41

5.3 力学性能 ........................................................................................................................... 42

5.4 小结 ................................................................................................................................... 44

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摘要：

摘要聚苯乙烯-聚乙烯/丁烯-聚苯乙烯三嵌段共聚物(SEBS)是一种典型的热塑性弹性体，具有良好的弹性和可反复成型加工的优点，有着广泛的应用前景。SEBS的硬段与软段易缠结，常需进行充油处理以提高在成型加工时的流动性。然而，操作油的加入会致使SEBS热稳定性和力学性能下降，且极易燃烧，存在火灾隐患。提高SEBS及其共混材料的力学性能以及阻燃性能已成为其应用领域的研究热点。本论文采用我国丰产的蒙脱土，结合热稳定优良的有机插层剂，并利用其片层的纳米效应，制备了SEBS/蒙脱土纳米复合材料。本文首先采用热稳定性高且具有阻燃效应的有机磷盐对蒙脱土进行有机插层处理，以克服常规的有机铵盐改性的蒙脱土热稳定性...

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