中文摘要：

以甲基丙烯酸酯改性硅油（分子量900）、甲基丙烯酸异冰片酯（IBMA）和脲烷二甲基丙烯酸酯（UDMA）为原料,在硫醇作为链转移剂的条件下,通过溶液聚合法合成了一种有机硅改性纳米凝胶（Si15M）。利用核磁共振氢谱（1H-NMR）、核磁共振硅谱（29Si-NMR）、傅里叶红外光谱（FT-IR）、凝胶渗透色谱（GPC）和透射电镜（TEM）对纳米凝胶进行了表征,确定了纳米凝胶的结构。元素分析,X射线光电子能谱分析（XPS）,黏度、硬度和接触角的测试结果表明：有机硅纳米凝胶具有一定的自上浮能力,在三乙二醇二甲基丙烯酸酯（TEGDMA）体系中可自发形成浓度梯度,进而调控梯度光聚合,通过光照可获得组成和硬度呈梯度变化的聚合物;随着纳米凝胶在TEGDMA体系中含量的增加,体系黏度随之增加,且黏度的增加会降低其上浮能力;纳米凝胶能够在光固化膜表面富集,有效降低其表面能,获得更为疏水的表面。

英文摘要：

A polysiloxane-eontaining nanogel has been prepared by solution polymerization with methaerylate-modi- fled polysiloxane （Mn =900）, urethane dimethacrylate （UDMA） and isobornyl methaerylate （IBMA） in the presence of a thiol chain transfer agent. The nanogel structure was characterized by proton nuclear magnetic resonance （IH- NMR） spectroscopy, silicon nuclear magnetic resonance （29 Si-NMR） spectroscopy, Fourier transform-infrared spec- troscopy （FT-IR）, gel permeation chromatography （GPC） and transmission electron microscopy （TEM）. It was demonstrated by elemental analysis, X-ray photoelectron spectroscopy （XPS）, viscosity, hardness and contact angle tests that the nanogel has a self-floating capability and can spontaneously form a concentration gradient in the triethyl- ene glycol dimethaerylate （TEGDMA） monomer, thereby controlling the gradient polymerization under UV irradiation and affording a polymer with gradient changes in composition and hardness. With the increase of the nanogel content in TEGDMA, the viscosity of the system increases, resulting in the decrease of the self-floating capability of the nano- gel. The nanogel can also become enriched on the polymer surface which reduces the dispersion surface energy and generates a more hydrophobic surface.