Abstract:We prepared pyridine-2,6-bis(ethyl)ester [BEP] and pyridine-2,6-bis(diethylamide) [BDP] polymers with polycarbonate backbones by ring-opening polymerization of the pyridinebis(ethyl)ester and pyridine-bis(diethylamide) units appended to a cyclic carbonate via a glycol chain. The polymers were characterized by FTIR, NMR, UV/Vis absorption and fluorescence spectroscopy, as well as SEC, powder XRD, DSC, and TGA. The measured glass transition temperature (T g ) of the BEP polymer was shifted from -32°C to -7 and -8°C after coordination of the Eu III and Tb III ions, respectively. Similarly, the T g of the BDP

Abandoned cellulose was treated with acid to prepare Micro-Crystalline Cellulose (MCC) holding affirmative polymerization, which was then treated with 1,4–butanesultone (BS) to synthesize water-soluble Sulfo-Butylated Cellulose ether (SBC). The structure of the SBC was characterized by means of FT-IR, 1H NMR, SEM, and XRD, and its relationship to function was investigated based on the polymerization of MCC and Degree of Substitution (DS). SEM images of hardened cement were also studied. The results indicated that when the polymerization of the MCC was smaller than 96 and the DS greater than 0.375, SBC exhibited water-reduction. When sulfonated cellulose was mixed into the cement paste, its retarding effect slowed hydration early in the aging process, so that later the structure of hardened cement paste became more uniform and compact than that of control.

A surface grafting technique is reported for synthesis of poly(pentafluorostyrene) via reversible addition fragmentation chain transfer onto iron (iron oxide) particles. 4-Methoxydithiobenzoate is used for the RAFT chain transfer agent. The molecular weight, surface morphology, thickness, thermal properties, and monomer conversion of the grafted polymer are reported. The grafted poly(pentafluorostyrene)-iron particles show a higher thermal transition temperature compared to the nongrafted polymer because it is speculated that the covalent bond between the polymer backbone and the surface of the iron particles restricts the molecular mobility. The monomer conversion increases in proportion to the amount of chain transfer agent (CTA) concentration at early polymerization time. The grafted poly(pentafluorostyrene) shows a "hairy" like polymer architecture with fibril thickness in the range of 80 to 100 nm. A thin coating is expected to maintain the magnetic saturation properties of iron particles. To the best of our knowledge, this is the first time that poly(pentafluorostyrene) has been grafted onto the iron particles utilizing RAFT and 4methoxydithiobenzoate as a CTA.

In this paper, the preparation of a capsule-shaped cross-linked PEG/LACE copolymer by the cross-linking reaction of polyethylene glycol (PEG) and lauric acid cellulose ester (LACE) in the presence of toluene diisocyanate (TDI) is described. Characterization by FT-IR, NMR, TEM, SEM, DSC, TG, POM and WAXD was conducted on the prepared samples to investigate their structure, phase transition energy storage capability, crystal morphology, and thermal stability. The reaction solution of PEG and LACE was extracted and used for the preparation of a PEG/LACE copolymer film, followed by an analysis of its molding capability. Also, different compositions of core and wall of the capsule were analyzed by measuring the contact angles of the raw materials and the obtained PEG/LACE copolymer. The experimental results revealed that the prepared PEG/LACE copolymer was a capsule-shaped compound in which PEG was encapsulated by long chains of LACE, demonstrating an excellent molding capability.Additionally, this material exhibited a completely reversible phase transition with high enthalpy, moderate temperature and good thermal cycle stability, indicating that it is an ideal solid-solid phase transition material for energy storage.Scheme 1 Synthesis process of the cross-linked PEG/LACE copolymer. Fig. 1 FTIR spectra of: (a) Cell-OH, (b) LA, (c) LACE, (d) PEG and (e) the PEG/LACE copolymer with a PEG concentration of 74 wt%.