Yongqiang Guo#, Lei Zhang#, Kunpeng Ruan, Yi Mu, Mukun He and Junwei Gu*. Enhancing hydrolysis resistance and thermal conductivity of aluminum nitride/polysiloxane composites via block copolymer-modification. Polymer, 2025, 323: 128189. 2023IF=4.1.（2區(qū)化學(xué)期刊）
https://doi.org/10.1016/j.polymer.2025.128189
Abstract
The preparation of thermally conductive silicone rubber composites incorporating aluminum nitride (AlN) as fillers has attracted considerable attention. However, the high susceptibility of AlN to hydrolysis and its limited compatibility with the silicone rubber matrix present significant challenges that hinder the enhancement of the composite''s thermal conductivity. In this work, AlN was modified through surface functionalization via grafting with divinylbenzene-acryloyl chloride block copolymer (PDVB-b-PACl), followed by compounding with poly(methylhydrosiloxane) (PMHS) to fabricate thermally conductive AlN@PDVB-b-PACl/PMHS composites. The modification significantly improved the hydrophobicity of AlN@PDVB-b-PACl, as demonstrated by a contact angle of 134.1° compared to 26.4° for unmodified AlN. When the molecular weight of PDVB-b-PACl is 5000 g/mol, the grafting amount is 0.8 wt%, and the loading of AlN@PDVB-b-PACl is 85 wt%, the AlN@PDVB-b-PACl/PMHS composite exhibited an optimal thermal conductivity of 1.82 W/(m·K), an 810% improvement over that of PMHS (0.20 W/(m·K)), and outperformed AlN/PMHS composites (1.58 W/(m·K)) with the same AlN loading. Additionally, the tensile strength of the composite was 0.58 MPa, approximately 2.4 times greater than that of PMHS (0.24 MPa).
以氮化鋁（AlN）為填料制備導(dǎo)熱硅橡膠復(fù)合材料近年來受到熱捧，但其極易水解且與硅橡膠基體的相容性差，不利于復(fù)合材料導(dǎo)熱性能的大幅提升。本文以二乙烯基苯-丙烯酰氯二嵌段共聚物（PDVB-b-PACl）對AlN進(jìn)行表面功能化接枝改性（AlN@PDVB-b-PACl），再與聚甲基氫硅氧烷（PMHS）共混復(fù)合制備AlN@PDVB-b-PACl/PMHS導(dǎo)熱復(fù)合材料。AlN@PDVB-b-PACl的疏水性得到明顯提升，其與水的接觸角為134.1°，遠(yuǎn)高于AlN與水的接觸角（26.4°）。當(dāng)PDVB-b-PACl分子量為5000、接枝量為0.8 wt%，且AlN@PDVB-b-PACl的用量為85 wt%時(shí)，AlN@PDVB-b-PACl/PMHS復(fù)合材料兼具最優(yōu)的導(dǎo)熱性能，其λ為1.82 W/(m·K)，較純PMHS的λ（0.20 W/(m·K)）提高了810%，也優(yōu)于相同AlN用量的AlN/PMHS復(fù)合材料的λ（1.58 W/(m·K)）。其斷裂強(qiáng)度為0.58 MPa，約為純PMHS斷裂強(qiáng)度（0.24 MPa）的2.4倍。
論文亮點(diǎn)
1. 設(shè)計(jì)并合成了疏水且能提高AlN與PMHS界面相容性的二乙烯基苯-丙烯酰氯二嵌段共聚物（PDVB-b-PACl）。
2. 優(yōu)化PDVB-b-PACl分子量為5000 g/mol時(shí)，AlN@PDVB-b-PACl/PMHS復(fù)合材料的界面熱阻最低。
3. 當(dāng)AlN@PDVB-b-PACl的質(zhì)量分?jǐn)?shù)為85 wt%且其表面PDVB-b-PACl接枝量為0.8 wt%時(shí)，AlN@PDVB-b-PACl/PMHS復(fù)合材料的λ最高，為1.82 W/(m·K)，為純PMHS的λ（0.20 W/(m·K)）的9.1倍。
第一作者：郭永強(qiáng)、張磊
郵件地址：gyqnpu@nwpu.edu.cn、18695349879@163.com
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