Biominerals such as bones, teeth and seashells, very often have advanced material properties and are a source of inspiration for material chemists. As in biological systems acidic proteins play an important role in regulating the formation of CaCO 3 biominerals, we employ poly(amino acid)s to mimic the processes involved in the laboratory. Here we report on the synthesis of random aminoacid copolymers of glutamic acid (Glu), lysine (Lys) and alanine (Ala) using the ring opening polymerization (ROP) of their respective N-carboxy anhydrides (NCA). The synthetic approach yields a series of polymers with different monomer composition but with similar degrees of polymerization (DP 45-56) and comparable polydispersities (PDI 1.2-1.6). Using random copolymers we can investigate the influence of composition on the activity of the polymers without having OPEN ACCESSPolymers 2012, 4 1196 to take into account the effects of secondary structure or specific sequences. We show that variation of the Glu content of the polymer chains affects the nucleation and thereby also the particle size. Moreover, it is shown that the polymers with the highest Glu content affect the kinetics of mineral formation such that the first precipitate is more soluble than in the case of the control.

Disc type reinforced piezoelectric composite bimorphs with series connection were designed and the performance was investigated. The composite bimorphs (PZT/PA and PZT/PDMS (40/60 vol%)) were successfully fabricated by a compression molding and solution casting technique. The charge developed at an applied force of 150 N is 18150 pC (PZT/PA) and 2310 pC (PZT/PDMS), respectively. Electric force microscopy (EFM) is used to study the structural characterization and piezoelectric properties of the materials realized. A clear inverse piezoelectric effect was observed when the bimorphs were subjected to an electric field stepped up through 2, 6 and 10 V, indicating the net polarization direction of the different ferroelectric domains. The as-developed bimorphs have the basic structure of a sensor and actuator, and, since they do not use any bonding agent for bonding, they can provide a valuable alternative to the present bimorphs where bonding processes are required for their realization that can limit their application at high temperature.

In this article, we report the modification of poly(styrene‐alt‐maleic anhydride) (PSMA) with monofunctional amine‐terminated poly(dimethyl siloxane) (PDMS–NH2) by thermal imidization, followed by the preparation and characterization of a surfactant‐free artificial latex thereof and application of this latex onto cotton fabric. The imidization reaction was monitored by NMR and attenuated total reflection Fourier transform infrared (ATR–FTIR) spectroscopy. 1,2‐Cyclohexyldicarboxylic anhydride was chosen as a model compound for the PSMA copolymer; this allowed a more detailed characterization by NMR and ATR–FTIR spectroscopy. After the PSMA/PDMS–NH2 imidization reached completion, a fraction of the anhydrides were ammonolyzed. In this way, a self‐emulsifying latex with an average particle diameter of approximately 145 nm and a ζ potential of −56 mV was obtained. It was found that the PDMS‐modified PSMA latex in which 30 mol% of the initial amount of anhydride groups were previously imidized by using PDMS‐NH2 and a fraction of the anhydrides were ammonolyzed with 0.3 eq. of NH3 (PSMA30) was stable in the pH range 4–10. The water contact angle values of the latex‐coated cotton textile fabric indicated a hydrophobized surface, with a static contact angle of 135.7°± 1.2°. The washing studies with a standard soap solution of the cotton samples with or without crosslinker showed that the crosslinked PSMA30 offered a good coating durability to the cotton. This waterborne resin based on surfactant‐free latices displayed promising properties for coating applications and seemed to be very suitable for the hydrophobization of polar surfaces. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

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