To imitate the superhydrophobicity of salient epicuticular wax on lotus leaves (hereafter "Lotus effect"), waxy dendrons were synthesized and subsequently grafted on amine-containing polystyrenes. To achieve a low surface energy and a specific surface morphology, the waxy dendron design is composed of two parts-the focal part possessing plenty of hydrogen bonding sites, and the peripheral part rich in van der Waals forces. The enhanced van der Waals force accompanied with increasing generation of dendrons helps induce self-assembly and phase separation in the preparation process of the polymer films. By different coating processes, three different films (thin film, honeycomb-like film, and three-dimensional rod-co-valley-like film) were obtained with contact angles of 95 degrees, 130 degrees, and 165 degrees, respectively. The three-dimensional rod-co-valley film samples were able to imitate the superhydrophobic property (i.e. Lotus effect), as well as utilize the built-in strong hydrogen bonds to adhere water droplets on surfaces or substrates

Three chromophore-containing dendrons were intercalated into montmorillonite layered silicates via an ion-exchange process. Enlarged d spacings ranging from 50 to 126 A were achieved for these novel organoclays. After the organoclays were blended with a polyimide, the steric bulkiness of the dendrons and the interaction between dendron and polyimide resulted in an ordered morphology. The orderly arranged nanocomposites were characterized by a UV-visible spectrophotometer, a variable-temperature infrared spectrometer, and electro-optical modulation. The dendrons in layered silicates were capable of undergoing a critical conformational change into an ordered structure, indicated by the drastic changes of interlayer distances at certain packing densities. Electro-optical coefficients increased sharply from 0 to 6 pm/V while the conformational change occurred. Furthermore, the addition of a polyimide capable of interaction-induced orientation was found to exert an enhancing effect on the degree of the noncentrosymmetric alignment.

In this study, thermally reversible polyurethanes (PUs) with shape memory effect were developed by using hydrogen bonding to enhance physical interactions. Two different types of PUs were synthesized: (1) a linear PU whose hard segment consists of methylene di-para-phenyl isocyanate (MDI) and di(ethylene glycol) (DEG); its soft segment is made of Tone 0260 polyol, a polyester polyol; (2) a side-chain dendritic PU which replaces DEG with different generations of dendritic chain extenders. By incorporation of the dendritic structure with peripheral long alkyl chains (strong van der Waals forces), the miscibility between hard and soft segments can be significantly improved. Consequently, the hydrogen bonding reinforced hard segments (malonamide linkages) of side chain dendritic PUs result in greatly enhanced mechanical properties and shape memory effect. During cyclic shape memory tests, one of the series can effortlessly achieve complete recovery in less than 10 second without any deficiency