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A kind of carbon nanotubes reinforced self-healable polythiourethane composite material with super-high lap shear strength, extremely high elongation at break, excellent optical transparency and improved thermal conductivity was presented.

The porous UHMWPE were prepared by wet process and biaxial stretching. The scanning electron microscopy (SEM) experimental results indicated that there were two discernible components: microfibril bundles and microfibril networks in the porous biaxial UHMWPE. The higher draw ratio along the longitudinal direction (the machine direction) contributed more to orientation of the UHMWPE fibrils. Along the transverse direction, fibrils were torn, and more microfibrils network with larger size formed. The mechanical test results showed that along the longitudinal direction, the UHMWPE exhibited higher tensile strength and lower elongation-at-break.

It is reported that a pitch gradient is formed in a side chain cholesteric liquid crystalline polymer (ChLCP) through a novel method. Heating up the ChLCP within the temperature range of the cholesteric (Ch) phase leads to the first availability of its planar texture. Then, the ChLCP film with the planar texture is cooled down to its glassy (G) state in line with the temperature difference between the upper and the bottom substrates. The SEM image indicates clearly a pitch gradient perpendicular to the substrates, and the results of transmission spectra show that the reflective bandwidth of the ChLCP film with the pitch gradient is greatly broadened.

The porous Ultra-high Molecular Weight Polyethylene (UHMWPE) is designed to fabricate the roadside safety devices fixed on the conventional metal or concrete road highway guardrails. When the UHMWPE with pores is shocked, the material is compressed because the pores are closed and much energy is absorbed. Next, elastic deformation and plastic deformation happen further under the stress, kinetic energy is transformed into deformation energy further. The cushioning capacity of UHMWPE will be improved when the pores are induced. Then the vehicles will not be destroyed seriously when they bounce. On the other hand, it will be convenient to fix the roadside safety devices on the conventional metal or concrete road highway guardrails and the cost must be lower than changing the whole guardrails. Experimental results indicate that: UHMWPE exhibited excellent shock-absorbing capacity and it was a promising roadside safety material.

Microscopic and macroscopic deformation behavior of ultra-high molecular weight polyethylene (UHMWPE) under the drawing force was studied in this paper. The scanning electron microscopy (SEM) experimental results indicated that: under the force, non-crystalline materials distorted, crystal faces were torn along grain boundaries and crystal grains were disrupted. So crystal size became smaller, more grain boundaries and more voids were formed, which supplied more free space for the movement of crystal grains and chain segments. The torsion test results showed that the UHMWPE exhibited excellent flexibility and the specimen had more excellent deformation ability at a slower loading rate.

A simple process to fabricate porous polyimide membranes (PPMs) and effect of warm-up temperature rates on morphologies of the PPMs were reported in this paper. The polymer solution layer consisting of the corresponding polyamic acid (PAA), solvent and the pore forming agents with high boiling temperature or high decomposition temperature was first treated under a lower temperature (about 150°C). The received solid membrane was further imidized by a higher temperature (about 270°C) and the pore forming agents were removed from the membrane at a temperature above their boiling temperature or decomposition temperature at last. Then a PPM was obtained. As the temperature was elevated gradually, the porosity of the received PAA membrane was lower than that of the PPM treated by a faster warm-up temperature rate.

A novel experimental route to fabricate porous polyimide membranes (PPMs) with ideal air permeability was reported. The polymer solution layer consisting of the corresponding polyamic acid (PAA), solvent, and dibutyl phthalate (DBP) with a boiling temperature of 340°C was treated by a simple process. The polymer solution layer was first treated at a lower temperature (about 150°C), then the received solid membrane was further imidized at a higher temperature (about 270°C), and finally, DBP was removed from the membrane at a temperature above its boiling temperature. The final asymmetric polyimide membrane with a dense skin layer was obtained. To improve the air permeability of the polyimide membranes, the polymer solution layer was treated between two substrates. And the PPMs with open pores on both sides are fabricated and the air permeability of the films is improved greatly.

Based on virtual prototyping technology (VPT) and software engineering principles, and combining with the characteristics of steam jet pump, a virtual prototyping development platform of steam jet pump, consisting of five functional models, including general scheme design, virtual physical prototype design, virtual performance prototype design, assemble process analysis and VR model design and evaluation, was present in this paper. The architecture and functional model of the virtual steam jet pump prototyping development platform (VSJPDP) were proposed in the article. The ideas corresponding to several key technological problems for implementing the VSJPDP were also described. At last, the platform’s feasibility, effectiveness and advancement were verified by the development process of the virtual single-stage steam jet pump.