PDF(Pubmed)
Abstract：
Waterborne polyurethane asphalt emulsion (WPUA) is an environmentally friendly bituminous material, whose performance is highly dependent on the phase structure of the continuous phase. In this paper, WPUAs in the vicinity of phase inversion were prepared using waterborne polyurethane (WPU) and asphalt emulsion. The chemical structures, thermal stability, dynamic mechanical properties, phase-separated morphology and mechanical performance of WPUAs were studied. Fourier-transform infrared (FTIR) spectra revealed that there are no -NCO bonds in either the pure WPU or WPUAs. Moreover, the preparation of WPUA is a physical process. The addition of WPU weakens the thermal stability of asphalt emulsion. WPU improves the storage modulus of asphalt emulsion at lower and higher temperatures. The glass transition temperatures of the WPUA films are higher than that of the pure WPU film. When the WPU concentration increases from 30 wt% to 40 wt%, phase inversion occurs; that is, the continuous phase shifts from asphalt to WPU. The WPUA films have lower tensile strength and toughness than the pure WPU film. However, the elongations at break of the WPUA films are higher than that of the pure WPU film. Both the tensile strength and toughness of the WPUA films increase with the WPU concentration. Due to the occurrence of phase inversion, the elongation at break, tensile strength and toughness of the WPUA film containing 30 wt% WPU are increased by 29%, 250% and 369%, respectively, compared to the film with 40 wt% WPU.
摘要：
水性聚氨酯沥青乳液(WPUA)是一种环保型沥青材料,其性能高度依赖于连续相的相结构。在本文中,使用水性聚氨酯（WPU）和沥青乳液制备了相转化附近的WPUA。化学结构，热稳定性，动态力学性能，研究了WPUAs的相分离形态和力学性能。傅里叶变换红外（FTIR）光谱显示，在纯WPU或WPUA中都没有-NCO键。此外，WPUA的制备是一个物理过程。WPU的加入削弱了沥青乳液的热稳定性。WPU提高了沥青乳液在较低和较高温度下的储能模量。WPUA膜的玻璃化转变温度高于纯WPU膜的玻璃化转变温度。当WPU浓度从30重量%增加到40重量%时，发生相转化；也就是说，从沥青到WPU的连续相变。WPUA膜具有比纯WPU膜更低的拉伸强度和韧性。然而,WPUA膜的断裂伸长率高于纯WPU膜的断裂伸长率。WPUA膜的拉伸强度和韧性均随WPU浓度的增加而增加。由于相反转的发生,断裂伸长率，含有30重量%WPU的WPUA薄膜的拉伸强度和韧性提高了29%，250%和369%，分别,与具有40重量%WPU的膜相比。
