标题: 藉由高分子氢键作用力的转换来控制高分子薄膜表面特性之研究
Tuning polymer surface free energy through mediating polymer hydrogen bonding interaction
作者: 廖春雄
张丰志
应用化学系硕博士班
关键字: 氧代氮代苯并环己烷;表面自由能;氢键;benzoxazine;surface free energy;hydrogen bonding
公开日期: 2008
摘要: 摘要

本论文中以讨论高分子氢键作用力及多面体聚矽氧烷奈米粒子对于高分子薄膜表面特性的为主体,分为五大主题:

1. 利用低温交联的Polybenzoxazine薄膜去修饰高分子薄膜表面
在我们以前的研究发现Polybenzoxazine薄膜为一低表面能材料,可以用来修饰无机固体表面如金属、玻璃或矽晶圆等等。但是对于高分子材料其热交联制程温度太高因此无法去修饰高分子表面。在本章中我们发现AIBN此自由基起始剂在120℃制程下由于起始剂化学键断键所产生的热能可以产生一些寡聚物,而这些寡聚物会对热交联反应产生催化效果。因此我们利用此低温制程成功的修饰高分子基材,史的这些高分子表面也具有低表面能特性。

2. 控制Polybenzoxazine薄膜表面能之研究
Polybenzoxazine 薄膜由于具有极强的高分子内氢键而拥有极低的表面能,我们利用了热与紫外光这两种方式来控制Polybenzoxazine薄膜中分子内与分子间作用力的比例。 藉由这两种方式我们可以轻易的控制Polybenzoxazine薄膜的表面能。此外,我们更利用紫外光照时间与区域的不同在Polybenzoxazine薄膜 上制造亲疏水性图案的阵列与梯度。并且成功的制造出鍗化镉量子点的规则阵列。
3. 制造拥有超疏水及超亲水特性的Polybenzoxazine 有机无机混成表面
我们利用混掺二氧化矽奈米粒子提高表面粗糙度以制造具有莲花效应的超疏水表面。再利用紫外光照让某些特定区域形成超亲水的表面,藉此我们可以得到同时具有超疏水及超亲水两种极端特性的表面。此外,在紫外光照后我们发现表面对于水滴产生极强的吸附力。我们将表面光照后产生的此特性应用在能转移微小水滴的机械手臂上。此外我们更利用表面分析化学分析影像能谱仪对光照后的表面化学组成改变作更深入的探讨。
4. 分子量及高分子氢键作用力对于低表面能材料Poly(4-vinyl phenol)表面特性影响之探讨
在我们先前研究发现Poly(4-vinyl phenol)为一低表面能材料。在此章中我们更深入的探讨分子量、多面体聚矽氧烷奈米粒子及高分子氢键作用力对于Poly(4-vinyl phenol)高分子薄膜表面特性的影响。为了探讨高分子氢键的影响我们合成了不同比例的Poly(4-vinyl phenol)/Poly(methyl methacrylate) 团块块体共聚合物及不规则共聚合物。在其中我们发现 Poly(4-vinyl phenol)/Poly(methyl methacrylate) 团块块体共聚合物及不规则共聚合物系统不同于混掺系统呈现非常低的表面能,这是因为团块块体共聚合物及不规则共聚合物系统在热处理在快速冷却的过程中降低了分子间的作用力。而混掺系统虽然也降低了Poly(4-vinyl phenol)之间的分子作用力却也增加了Poly(4-vinyl phenol)与Poly(methyl methacrylate)分子链之间的作用力。所以混掺系统的表面能会随着Poly(methyl methacrylate)的含量增加而增加。

5. 多面体聚矽氧烷奈米粒子对于poly(4-vinyl phenol)表面特性与溶液相行为影响之探讨
多面体聚矽氧烷奈米粒子本身为一具有低表面能的奈米粒子,所以不管当我们是混掺或是接枝上去poly(4-vinyl phenol)此种高分子上面,我们均发现随着多面体聚矽氧烷奈米粒子的量越多,高分子薄膜的表面能降的越低。此外我们也发现在末端带有多面体聚矽氧烷奈米粒子的Poly(4-vinyl phenol) 团块块体共聚合物在溶液中呈现非常独特的自组装行为。
Abstract

In this study, we focus on five major subjects which based on the effect of hydrogen bonding and POSS nanoparticle on surface free energy:

1. Modification of Polymer Substrates with Low Surface Free Energy Material by Low-Temperature Curing Polybenzoxazine
The B-ala/AIBN PBZ system has a higher extent of the ring-opening of oxazine because phenol-containing oligomers are formed at the early stage of the curing process. As a result, the B-ala/AIBN PBZ system possesses a relatively stronger intramolecular hydrogen bonding and lower surface energy than the pure B-ala system at low temperature curing. In this context, Poly(4-vinyl pyridine), Poly(4-vinyl phenol) thin film and polycarbonate substrates which lack liquid resistance possess low surface free energy after modification with B-ala/AIBN = 5/1 PBZ.
2. Tuning the Surface Free Energy of Polybenzoxazine Thin Films
A novel approach to manipulate the surface free energy and wettability on polybenzoxazine thin films can be achieved simply by varying time of thermal treatment or UV exposure. Fraction of the intramolecular hydrogen bonding of the as cured sample will convert into intermolecular hydrogen bonding upon thermal treatment or UV exposure and thus results in increase of hydrophilicity and wettability. This UV approach provides a simple method to generate wettability patterns or wettability gradients on the surface of polybenzoxazine film. In addition, we have applied this technique to the preparation of a large-area periodic array of CdTe colloidal nanocrystals on polybenzoxazine thin films.

3. Fabrication of patterned superhydrophobic Polybenzoxazine-hybrid surfaces
The hydrophilicity of B-ala PBZ film and superhydrophobic polybenzoxazine-hybrid surface can be controlled through UV exposure to change ratio of intra- to intermolecular hydrogen bonds. Fraction of the intramolecular hydrogen bonding of the as cured sample will convert into intermolecular hydrogen bonding upon UV exposure and thus results in increase of hydrophilicity. This simple method allows for manipulating the hydrophilicity at selected regions on superhydrophobic polybenzoxazine-hybrid surface to create patterned surface with superhydrophobic and superhydrophilic regions. Besides, we have found that the superhydrophobic polybenzoxazine-silica hybrid surface exhibits good adhesion of water droplets after UV exposure which can be served as a “mechanical hand” to transfer water droplets from a superhydrophobic surface to a hydrophilic one.
4. Effect of molecule weight and hydrogen bonding on low-Surface-Energy material of poly(vinylphenol)
We discovered that a series of poly(vinylphenol-co-methylmethacrylate) (PVPh-co-PMMA) block and random copolymers possess extremely low surface energy after a simple thermal treatment procedure, even lower than that of poly(tetrafluoroethylene) (22.0 mJ/m2) calculated on the basis of the two-liquid geometric method. The decrease of the intermolecular hydrogen-bonding fraction between hydroxyl groups of PVPh in PVPh/PMMA systems through a simple thermal treatment procedure tends to decrease the surface energy and the sequence distribution of the vinylphenol group in PVPh-co-PMMA copolymers plays an important role in dictating the final surface energy after thermal treatment.

5. Effect of POSS nanoparticle on Surface Free Energy and Phase Behavior
POSS-PAS copolymer was systhesed by atomic transfer radical polymerization with POSS-Cl initiator as a macroinitiator which was obtained by using corner-capping reaction. POSS-PVPh copolymer was obtained from the hydrolysis of POSS-PAS copolymer. We found that the POSS nanoparticle would decrease the polymer surface free energy in both POSS/PVPh and POSS-PVPh systems. With incrasing the content of POSS nanoparticle on polymer thin film surface the surface free enegy of polymer thin film would decrease dramatically. We also found that the POSS-PVPh copolymers possessed unique phase behavior in solution state and the superhydrophobic surface was prepared from POSS-PVPh in a THF/toluene mix solution.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT079325506
http://hdl.handle.net/11536/40596
显示于类别:Thesis


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