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In this article, we report a robust strategy to prepare polymer composites with enhanced thermal conductivity and mechanical properties for geothermal heat pump pipes, in which high density polyethylene (HDPE) used as matrix, various inorganic fillers including zero-dimensional (0D) aluminium spherical particles (Al-SPs), one-dimensional (1D) carbon fibres (CF) and two-dimensional (2D) graphite platelets (GPs), used alone or blended as modifier. The as-prepared polymer composites are GPs/HDPE, GPs/CF/HDPE, GPs/Al-SPs/HDPE and GPs/CF/Al-SPs/HDPE. Thermal conductivity and mechanical properties of these polymer composites were characterised. The results indicate that of all these as-prepared polymer composites, GPs/CF/Al-SPs/HDPE composites are the only one which possesses preferable and comprehensive properties both in thermal conductivity and mechanical properties due to the synergistic effect of filler. The thermal conductivity, elongation at break and tensile strength of GPs/ CF/Al-SPs/HDPE composites prepared with GPs (9 wt%), CF (3 wt%) and Al-SPs (3 wt%) were 0.803 W m−1K−1, 70.6 % and 26.69 MPa, respectively, which could meet the commercial requirements of the geothermal heat pump pipes.

This paper used wheat straw and palygorskite clay as raw materials, and phenolic resin as adhesive. By the technologies of powdering, mixing, solidifying, molding and sintering, the palygorskite clay Modified woodceramics were obtained. And it made use of these porous composite materials to research the adsorption of the phenol wastewater, which explored the adsorption effect of the composite materials on phenol and found out the optimum conditions of adsorption by changing the ratio of raw materials, sintering temperature, dosage of composite materials, oscillating time and pH. The result of the palygorskite clay Modified woodceramics prepared by different dosing ration of raw materials and sintering temperatures on phenol showed that the removal effect of the composite materials (wheat straw: palygorskite clay=5:1, sintering temperature = 900 °C) on phenol was best. Using the palygorskite clay modified woodceramics to adsorb the phenol wastewater. It turned out that when the dosage of the composite materials was 0.5 g, the Oscillating time was 60 mins, and the solution temperature was 25 °C, the composite materials adsorption efficiency on phenol was the highest. In addition, the higher the phenol solution concentration and pH, the lower the adsorption efficiency was. What's more, the absorbability of the composite materials on phenol corresponded with Feundlich adsorption model, and the saturated adsorption was 45.66 mg/L, which indicated that the palygorskite clay Modified woodceramics had strong adsorption effect to phenol.