Tetrahomocorona[2]arene[2]tetrazines were constructed by means of a fragment coupling strategy based on nucleophilic aromatic substitution reaction starting from 3,6-dichlorotetrazine and o-, m-, and p-bis(hydroxymethyl)benzenes. The unprecedented macrocycles gave rectangular box-like cavities with tunable cavity sizes and deficient electronic properties depending on the substitution pattern of phenylene. Due to anion-π interactions, they formed complexes selectively with azide and thiocyanate owing to complementary shapes between host and guest.

A novel terpolymer 2‐acrylamide‐2‐methylpropanesulfonic acid/acrylamide/sodium styrene sulfonate (AMPS/AM/SSS), used as fluid loss agent for oil well cement under high temperature, was prepared with initiator of azobisisobutryamide chloride. The optimum reaction conditions of polymerization were obtained from the orthogonal experiments, reaction temperature 40°C, initiator 0.1 wt%, molar ratio of monomers AMPS/AM/SSS 20/5/1. The structure and performance of terpolymer was characterized with Fourier transform infrared spectrometer, nuclear magnetic resonance hydrogen spectrum, thermogravimetric and simultaneous differential thermal analysis, high‐temperature and high‐pressure water loss meter, and rotational viscometer, indicating that the terpolymer was perfectly synthesized and started to decompose at 350°C and showed good performance of fluid loss control up to 160°C. The ζ‐potential instrument and scanning electron microscopy were used to investigate the mechanisms of fluid loss control, indicating that the terpolymer can prevent the generation of flocculated structure in the cement and reduce the porosity of the filter cake. These results have important referential value for developing new high‐temperature‐resisting fluid loss agents. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers

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