Biomineralization II (eBook)

Preface 9
Contents 11
Bio-inspiredMineralization Using Hydrophilic Polymers 13
1 Introduction 15
2 Different Crystallization Modes and Ways to Modify Crystallization 17
3 Polymer-Controlled Crystallization 34
4 Conclusion 76
5 Current Trends and Outlook to the Future 78
References 80
Bio-inspired Crystal Growth by Synthetic Templates 90
1 Introduction 91
2 Basic Principles of Crystal Growth 92
3 Synthetic Template Controlled Crystal Growth 95
4 Synergistic Effects of Crystal Growth Modifiers 107
5 Artificial Interfaces and Matrices for Crystallization 110
6 Summary and Outlook 122
References 123
Delayed Action of Synthetic Polymers for Controlled Mineralization of Calcium Carbonate 130
1 Introduction 131
2 Calcium Carbonate 134
3 Multi-Step Nucleation and Growth in the Mineralization Process 140
4 Delayed Action for Nucleation and Growth of CaCO3 143
5 Template Mineralization on the Surface of Calcium Carbonate 158
6 Conclusions and Outlook 161
References 162
Inorganic–Organic Calcium Carbonate Composite of Synthetic Polymer Ligands with an Intramolecular NH···O Hydrogen Bond 166
1 Introduction 167
2 pKa Shift by Neighboring Amide NH Through a Hydrogen Bond 172
3 Increase of Formation Constant by pKa Shift 173
4 Partially Covalent Ca – O Bond in Carboxylate and Phosphate Ca(II) Complexes 175
5 Weak NH · · · O Hydrogen Bond in Sulfonate Ca(II) Complexes 177
6 Strong NH · · · O Hydrogen Bond in Carboxylate Ca(II) Complexes 178
7 Structural Transformation by Rearrangement of Hydrogen Bond Networks 180
8 Ca Cluster with Synthetic Chelating Ligand 184
9 CaCO3/Polycarboxylate Composites as Models of Biominerals 185
10 CaCO3 Composites with NH · · · O Hydrogen Bonds in the Polymer Main Chain 186
11 Location of Strongly Binding Polycarboxylate on the Surface of a CaCO3 Crystal 187
12 Dependence of the CaCO3 Composite on Polymer Ligand Tacticity 191
13 Biological Relevance of Synthetic Polymer Ligands 193
14 Nanocomposite of the Nacreous Layer in Pinctada Fucata 194
15 Variation of Metal–O Bonding by Conformational Change of Carboxylate Ligands 195
16 Proton-Driven Conformation Switch in Asp-Oligopeptide and Model Compounds 196
17 Binding Regulation of Polycarboxylate on CaCO3 Crystals by Conformational Change 198
18 Conclusions 199
References 200
Author Index Volumes 251–271 205
Subject Index 215

Delayed Action of Synthetic Polymers for Controlled Mineralization of Calcium Carbonate (p. 119-120)

Abstract Natural inorganic–organic hybrid materials are formed through mineralization of inorganic materials on self-assembled organic materials. In these mineralized tissues, crystal morphology, size, and orientation are determined by local conditions and, in particular, the presence of "matrix" proteins or other macromolecules. The final crystalline phase arises through a series of steps initiated by the formation of an amorphous phase that undergoes subsequent phase transformations. The multi-step crystallization process on living systems was supported by the detection of different mineral polymorphs in natural organisms and subsequent phase transformation. This work focuses on a new concept for controlling crystal polymorphs by delayed action of organic additives during nucleation stages. During the formation of continuous thin films of minerals, several authors have used a phase-transformation process from an initially deposited amorphous phase to crystalline phase. The delay addition method gives a new simple process for controlling the CaCO3 crystallization. Three different crystal polymorphs of CaCO3 (aragonite, vaterite, and calcite) were selectively induced by changing the time when the radical initiator was added to a calcium carbonate solution with sodium acrylate. These processes may be similar to the secretion of specific proteins or molecules during the transformation of biomineralization.

Keywords Calcium carbonate · Delay addition · In situ polymerization · Latent inductor · Transformation

Abbreviations
ACC amorphous calcium carbonate
DMSO dimethyl sulfoxide
FT-IR Fourier transform infrared spectroscopy
h hour(s)
KPS potassium peroxodisulfate
L liter(s)
min minute(s)
mol mole(s)
Mw weight average molecular weight
PAA poly(acrylic acid)
PAZO polyazobenzen
PVP poly(N-vinylpyrrolidone)
SEM scanning electron microscopy
TEM transmission electron microscopy
XRD X-ray diffraction
UV ultra violet

1 Introduction

The design of nanomaterials, in other words, hybrid materials, has emerged as one of the most exciting areas of scientific effort in this decade. Among various research fields aimed at constructing nanomaterials, organic–inorganic hybrid materials have opened a new horizon in the field of materials science. When different materials are hybridized at the nano-meter scale, the obtained hybrid materials show unique properties compared with microscale composites [1–3]. Organic–inorganic hybrids have been elaborated with various inorganic hosts such as inorganic clay compounds [4], metal oxo clusters [5], oligosilsesquioxanes and their derivatives [6], zeolite [7], and metal [8] nanoparticles. Among them, sol-gel reaction of metal alkoxides is a widely used technique for the preparation of the organic–inorganic hybrid materials [9–11]. One of the most important advantages of the sol-gel process for preparation of the hybrids is the milder process compared with the normal glass preparation method. The mild characteristics offered by the sol-gel reaction allow the introduction of organic components inside the inorganic network. Organic–inorganic polymer hybrids can be prepared by mixing organic polymer into the sol-gel reaction. To obtain homogeneous organic– inorganic hybrids, in which the organic polymer is dispersed in the inorganic matrix at the nano or molecular scale, increased compatibility between the organic polymer and inorganic phases is necessary. The introduction of covalent bonds or chemical and physical interactions between the organic polymers and the inorganic units are efficient at increasing compatibility.