环氧改性聚硅氧烷污损释放涂层的制备及其力学性能研究

Preparation and Mechanical Properties of Epoxy Modified Polysiloxane Fouling Release Coating

目的以有机硅树脂为基体树脂,环氧树脂作为改性剂,制备了一种力学性能较高且具有污损释放特性的防污树脂涂层。方法首先采用γ-氨丙基三乙氧基硅烷(APTES)和环氧树脂(E51)反应得到硅烷化环氧树脂(ME51);然后以甲基三氯硅烷(MTS)、二甲基二氯硅烷(DDS)和苯基三氯硅烷(PTS)为原料,通过水解-缩合法制备有机硅树脂(PMPS);最后将ME51添加到PMPS树脂中,经常温固化得到具有高力学性能和低表面能特性的环氧改性硅树脂(MPMPS)。系统地研究了环氧含量对MPMPS树脂涂层力学性能和防污性能的影响。结果与PMPS相比,当环氧含量(均以质量分数计)为30%时,MPMPS涂层的铅笔硬度从HB提升至4H,抗冲击性从30cm提升至60cm,柔韧性仍保持在3mm,附着力从1.3MPa提升至3.6MPa,25℃下储能模量从206MPa提升至503MPa。MPMPS树脂涂层不仅具有良好的力学性能,还具有较低的表面自由能(24.66 mJ/m^(2));MPMPS在抗芽孢杆菌黏附实验、抗三角褐指藻黏附实验和90 d浅海浸泡的防污实验中,表现出与PMPS同样优异的污损释放性能。结论当环氧含量为30%时,MPMPS涂层表现出最佳的力学性能,同时具有良好的防污性能。

Fouling release coating represented by silicones appears to be a promising non-toxic alternative to the coatings containing biocide or toxic compounds.It has great application prospect and potential in the field of antifouling.However,traditional silicone-polysiloxanes suffer from poor mechanical properties and insufficient adhesion.The work aims to enhance the insufficient mechanical properties and adhesion of silicones.The compatibility of epoxy resin and silicone resin was improved by silane coupling agent reacting with epoxy resin.An antifouling resin coating with improved mechanical properties and fouling release properties was prepared,with silicone resin as matrix resin and epoxy resin as modifier.Firstly,a silanized epoxy resin(ME51)was synthesized by reactingγ-aminopropyltriethoxysilane(APTES)with epoxy resin(E51).Then,the silicone resin(PMPS)was prepared by hydrolysis-condensation method,with methyltrichlorosilane(MTS),dimethyldichlorosilane(DDS)and phenyltrichlorosilane(PTS)as raw materials.Finally,the obtained epoxy-modified silicone resin(MPMPS),which had high mechanical properties and low surface energy characteristics,was obtained by adding ME51 to the PMPS resin and curing at room temperature.The chemical structures of PMPS and MPMPS were characterized by Fourier transform infrared spectroscopy(FT-IR).The coating pencil hardness,flexibility and impact resistance tests were carried out with reference to national standards.The dynamic mechanical properties,glass transition temperature and modulus of the coatings were tested by a dynamic mechanical analyzer(DMA).The surface free energy of the coating was calculated by measuring the contact angle(CA).The 3D topography of the coating surface was observed by confocal laser scanning microscope(CLSM).The surface morphology and element distribution of the coating were analyzed and characterized by scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The shallow sea immersion test was carried out with reference to GB/T5370-2007.In order to observe the fouling release properties of the coatings,the test panels were rinsed in the last test.The mechanical properties,adhesion,surface free energy and surface morphology of the epoxy-modified silicone resin coating synthesized in this work were closely related to the epoxy content.When the epoxy content was less than 30wt.%,with the increase of epoxy content,the hardness,flexibility and impact resistance of MPMPS coatings increased.Modulus,glass transition temperature and Tanδincreased.The adhesion of the coating to the substrate was significantly increased.When the epoxy content was greater than 30wt.%,with the increase of epoxy content,the hardness,flexibility,impact resistance and adhesion of MPMPS coating decreased obviously.Modulus,glass transition temperature and Tanδdid not increase significantly.When the epoxy content was 30wt.%,compared with PMPS,the pencil hardness of MPMPS coating increased from HB to 6H,and the impact resistance increased from 30 cm to 60 cm.MPMPS coating flexibility remained at 3 mm.The coating adhesion increased from 1.3 to 3.6 MPa,and the storage modulus at 25℃increased from 206 to 503 MPa.MPMPS coating not only had good mechanical properties,but also had low surface free energy(24.66 mJ/m^(2)).MPMPS showed the same excellent fouling release performance as PMPS in the anti-Bacillus adhesion test,anti-Phaeodactylum tricornutum adhesion test and 90-day shallow sea immersion antifouling test.In summary,an epoxy-modified silicone resin is successfully synthesized.When the epoxy content is 30wt%,the MPMPS coating exhibits the best mechanical properties and antifouling properties.The work provides theoretical support and reference for the application of modified silicone resin in the field of antifouling.