Materials combining high stiffness and mechanical energy dissipation are needed in automotive, aviation, construction, and other technologies where structural elements are exposed to dynamic loads. In this paper we demonstrate that a judicious combination of carbon nanotube engineered trusses held in a dissipative polymer can lead to a composite material that simultaneously exhibits both high stiffness and damping. Indeed, the combination of stiffness and damping that is reported is quite high in any single monolithic material. Carbon nanotube (CNT) microstructures grown in a novel 3D truss topology form the backbone of these nanocomposites. The CNT trusses are coated by ceramics and by a nanostructured polymer film assembled using the layer-by-layer technique. The crevices of the trusses are then filled with soft polyurethane. Each constituent of the composite is accurately modeled, and these models are used to guide the manufacturing process, in particular the choice of the backbone topology and the optimization of the mechanical properties of the constituent materials. The resulting composite exhibits much higher stiffness (80 times) and similar damping (specific damping capacity of 0.8) compared to the polymer. Our work is a step forward in implementing the concept of materials by design across multiple length scales.

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Shape memory polymers are a promising class of stimuli-responsive materials that have dual-shape capability. This kind of materials can recover their shape in a predefined way from temporary shape to desired permanent shape when exposed to an appropriate stimulus. In the development and extensive application of synthetic shape memory polymers on textile industrials, the thermal and hygrothermal effects of wool materials have attracted considerable attention. In this article the fundamental concept of the shape memory polymers and the fundamental aspects of the shape-memory effect were reviewed. The thermal and hygrothermal effects of wool materials were also summarized to discuss the shape memory behavior of wool materials. Besides the effects of synthetic shape memory polymers on the thermal and hygrothermal of the woven wool fabrics were introduced to show the shape memory behavior of treated wool further.

To achieve bio-scouring or biological degumming of the flax roving, an alkalophilic strain was screened from the rotten wrack around Zhoushan archipelago sea area. Determination of enzyme activity showed that the activities of petinase and xylanase were obtained, and enzyme activities are stable under 50°C and at pH values in the range of 6.5 to 9.0. It was utilized to scour the flax roving under alkaline conditions, and the result showed that the strain had a good characteristic of scouring, and less strength loss of flax fiber was 14.19%. Scanning electron microscopy (SEM) showed that the gum in the flax fiber was mostly degraded, and the most smooth fiber surface was displayed, compared with fiber untreated and scoured by caustic soda.

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