改性松香对速生杨木性能提升的研究

Improvement of Properties of Fast-growing Poplar by Modified Rosin

以精制松香(RR)、聚合松香(PR)和丙烯酸松香(AAR)为改性剂,无水乙醇为溶剂,配制质量分数为20%的浸渍液,采用浸渍法对速生杨木进行改性,得到精制松香改性材(RRMW)、聚合松香改性材(PRMW)和丙烯酸松香改性材(AARMW),并以无水乙醇浸渍得到对照木材(CW)。采用红外光谱(FT-IR)、扫描电镜(SEM)、激光共聚焦显微镜(CLSM)和X射线衍射(XRD)等方法对改性材进行了结构表征,并测试了改性材的耐水性和机械性能。研究结果表明:改性材的红外光谱在1691 cm-1的CO吸收峰显著增强,XRD分析发现晶面衍射峰没有明显变化,SEM和CLSM图中可清晰地观察到改性松香沉积在木材细胞腔且渗入了木质细胞壁,表明改性松香已经进入木材细胞,但对木材纤维素的结构没有影响。性能测定结果发现:3种改性材的性能均有所提高,其中AAR对速生杨木的性能提升最显著,AARMW的耐水性明显增强,其浸渍12 d后的吸水率为79.68%,而对照木材的吸水率则为186.28%;AARMW在180 s时的接触角为88.78°,相比15 s时的100.09°,仅下降12%,而对照木材接触角由15 s时的44.34°降至180 s时的0°。此外,与对照木材相比,AARMW的静曲强度(MOR)、弹性模量(MOE)和顺纹抗压强度(CS)分别增加了18.09%、27.51%和17.85%,较好地提高了速生杨木的机械性能。

The tricyclic diterpene structure of rosin has unique properties.The fast-growing poplar was modified by using the refined rosin(RR),polymerized rosin(PR)and acrylic acid rosin(AAR)as madifier and ethanol as solvent to prepare the impregnating solution with the mass fraction of 20%.The fast-growing poplar was modified by impregnation method to obtain refined rosin modified wood(RRMW),polymerized rosin modified wood(PRMW),acrylic acid rosin modified wood(AARMW),and impregnated with absolute ethanol to obtain control wood(CW).The structure of the modified materials was characterized by infrared spectroscopy(FT-IR),scanning electron microscope(SEM),confocal laser scanning microscope(CLSM)and X-ray diffraction(XRD).The water resistance and mechanical properties of the modified materials were tested.The results showed that the CO absorption peak of the FT-IR for the modified material was significantly enhanced at 1691 cm-1.XRD analysis showed that the crystal plane diffraction peak had no obvious change.It was clearly observed in the SEM and CLSM images that the rosin was deposited in the wood cell lumen and infiltrated into the wood cell wall,which indicated that the modified rosin entered the wood cells,but had no effect on the structure of wood cellulose.The results of performance test showed that the properties of the three kinds of modified wood were improved,and the improvement of acrylic acid rosin modified wood was the most significant.The water resistance of AARMW was significantly enhanced,and the water uptake rate was 79.68%,while that of the control wood was 186.28%after 12 days of impregnation.The contact angle of AARMW was 88.78°in 180s,which was only 12%lower than 100.09°in 15s.However,the contract angle of control wood decreased from 44.34°at 15s to 0°at 180 s.In addition,compared with the control wood,the modulus of rupture(MOR),modulus of elasticity(MOE),and compression strength(CS)of AARMW increased by 18.09%,27.51%and 17.85%respectively,which showed that the mechanical properties of fast-growing poplar were obviously improved.