【作者】 王洪艳；

【导师】 杜官本；

【作者基本信息】 南京林业大学 ， 木材科学与技术， 2013， 博士

【摘要】 论文以云南省内代表性树种云南松和巨龙竹为研究材料，利用RF（N₂，O₂和Ar三种工作气体），DBD（工作气体为空气）冷等离子体处理云南松和巨龙竹，分析研究了每种冷等离子体处理，改善表面润湿性的最优工艺及时效性；采用SEM， XPS， FTIR分析研究了处理前后木竹材表面形貌和化学组成；研究了冷等离子体处理对木竹材胶合强度影响；同时利用DBD冷等离子体处理对云南松表面Fe3O4纳米材料构筑进行了探索性的研究。（1）冷等离子体处理材料表面，改善材料表面润湿性与冷等离子体类型和工艺参数密切相关。本研究中得到冷等离子体处理改善云南松和巨龙竹表面润湿性最优处理工艺分别为，N₂-RF冷等离子体：200W，2min（云南松）、300W，1min（巨龙竹）；O₂-RF冷等离子体：300W，3min（云南松）、200W，2min（巨龙竹）；Ar-RF冷等离子体：300W，3min（云南松）、300W，2min（巨龙竹）；空气DBD冷等离子体：4KW，7次（云南松）、4KW，3次（巨龙竹），传送带速度为12米/分。（2）云南松和巨龙竹经RF和DBD冷等离子体改性后，材料表面的接触角显著下降，表面润湿性和自由能明显提高。经RF和DBD冷等离子体改性后，云南松和巨龙竹表面的改性效果均存在时效性，即随着放置时间的延长改性效果下降，冷等离子体改性的时效性与工作气体和自身材料性质有关，本研究中云南松和巨龙竹的时效性变化基本一致，均在放置14天左右改性效果消失。等离子体改性后表面能存在时效性主要是因为表面极性力的丧失,这可能是由于木材表面产生的活性基团暴露在空气中逐渐被氧化造成的。为了保证冷等离子体改性效果，后续加工要在有效期内进行，时间间隔越短越好。（3） SEM观察的结果显示冷等离子体处理后云南松和巨龙竹表面有明显的等离子体蚀刻痕迹，表面明显粗化，N₂和O₂冷等离子体处理后对云南松和巨龙竹蚀刻效果比Ar和DBD等离子体处理明显。XPS分析结果显示，经冷等离子体处理后，云南松和巨龙竹均在表面有N元素推测以-NH2方式存在、O/C明显增加，其中经O₂冷等离子体处理后O/C大于其他等离子体处理；同时冷等离子体处理后材料表面C₁含量减少，C₂和C₃含量则明显增加，导致表面产生了大量的含氧官能团。FTIR的结果显示云南松和巨龙竹表面经冷等离子体处理后，材料表面O-H和C-O的特征峰增加，导致材料表面润性提高。（4）经冷等离子体最优工艺处理后，云南松和巨龙竹表面的胶合性能明显提高。试验中云南松经N₂冷等离子体处理后胶合强度提高幅度最大，达到75.83%；对于同种胶粘剂这四种冷等离子体处理效果依次为N₂>O₂>DBD>Ar。试验中同种冷等离子体处理后使用UF胶粘剂粘接性能提高幅度最大，其次是MUF，最后是MF。冷等离子体处理云南松和巨龙竹表面，材料表面胶合性能提高的主要原因是冷等离子体处理后，材料表面明显粗化，同时产生了-CO、-OH和-COOH等含氧官能团和亲水性官能团导致材料表面润湿性明显增加，有利于“胶钉”的形成和胶粘剂在材料表面的“扩散”和“吸附”。（5）经空气DBD冷等离子体处理后的云南松表面可以沉积Fe3O4纳米材料，此方法工艺简单，成本低廉，无污染，绿色环保。松木表面Fe3O4纳米材料的沉积量与沉积次数有关，本研究中沉积5次，每次20min，效果较好。沉积Fe3O4纳米材料的云南松具有明显的电磁屏蔽效果。更多还原

【Abstract】 In this study, the Pinus yunnanensis; Dendrocalamus sinicus, the two representative speciesin Yunnan province, were treated by N₂, O₂, Ar radio frequency discharge and airdielectric barrier discharge cold plasma. This paper studied the optimum process ofevery kind of cold plasma and then the surface aging behavior and activation time ofthe optimum process were also studied; the surface morphology changes andchemical composition changes of the wood and bamboo were analyzed using SEM,XPS and FTIR. The bonding perfomance of the wood and banboo that treated by coldplasma was studied and the magntic performance of wood treated by DBD coldplasma was also studied.The results shown in this study can be summarized as follows:（1） The improvement of the wettability of material surface treated by cold plasmais closely related to the process parameters. In this study, the optimumprocesses of every kind of cold plasma to improve the wettability of wood andbamboo are: N₂-RF cold plasma,200W,2min for Pinus yunnanensi;300W,1min for Dendrocalamus sinicus; O₂-RF cold plasma,300W,3min forPinus yunnanensi;200W,2min for Dendrocalamus sinicus; Ar-RF cold plasma,300W,3min for Pinus yunnanensi;300W,2min for Dendrocalamus sinicus; airDBD cold plasma,4KW,7times for Pinus yunnanensi;4KW,3times forDendrocalamus sinicus under the speed of12m/min..（2） The contact angles of the Pinus yunnanens and Dendrocalamus sinicus decrease;the surface wettability of the materials have been improved when treated bycold plasma. But the effect of surface modification that treated by the coldplasma decrease gradually with the time going on, and it is related to the kindof the cold plasma and the material. In this study the aging behavior trends areconsistent that the modification effect almost disappears about2weeks. Inorder to ensure the modification effect of the cold plasma, the subsequentprocessing should be carried out immediatedly.（3） The result of the SEM observation shows that the surface of the Pinusyunnanensis and Dendrocalamus sinicus become rough which have obvioustraces of plasma etching after cold plasma treatment. The plasma etching of thematerials treated by N₂, O₂cold plasma are more obvious than the others. Theresult of the XPS shows that the surface of the treated materials have N element, the atomic ratio O/C has increased which increasing most treated by O₂coldplasma, the content of C₁decreases while the content of C₂and C₃increasingwhich meant more groups are oxidized or more peroxides are formed on thesurface. The result of the FTIR shows that content of O-H and C-O increase ofthe material surface that treated by cold plasma.（4） The bonding performance of the wood and bamboo can been improved by coldplasma treatment. In this study the bonding strength of the Pinus yunnanensincreases largely treated by N₂-RF cold plasma, reaching to75.83%. For thesame adhesive, the ratio of bonding strength increasing for the four kinds ofcold plasma in this study is N₂>O₂>DBD>Ar, but for the same cold plasma, theincreasing for the different adhesives is UF>MUF>MF. The bondingperformance of the wood and bamboo can been improved after cold plasmatreatment is due to the the surface contact angle decreasing, the free energyincreasing, the wettability improving which is good for the formation of the“adhensive nail” and the diffusion and adsorption of adhensive on the materialsurface.（5） The magnetic Fe3O4/Pinus yunnanensis composite was prepared successfullyusing the DBD cold plasma which is a method of simple process, low cost, nopollution. The amount of the nano-Fe3O4is related to the times of immersion.In this study, the optimum process is the5times for20minutes each time, andthe Fe3O4/Pinus yunnanensis composite have good electromagnetic shielding.更多还原