Preparation And Properties Of Temperature-sensitive Bio-friendly Hybrid Nanoparticles

A new set of organic-inorganic hybrid temperature sensitive microgel particles were prepared through two methods.One uses precipitation prepared temperature sensitive microgel,and in situ hybrid with Hydroxyapatite(HAP).The other uses Reversible Addition-Fragmentation Chain Transfer(RAFT) preparing ABA block polymers,and disperses in water so hybrid with Hydroxyapatite(HAP),at last shell-core organic-inorganic hybrid temperature sensitive microgel particles were gained.Sphere and stable single dispersion temperature sensitive microgels were obtained using N-vinylcaprolactam,N-vinylpyrrolidone and N,N'-methylenebisacrylamide by Precipitation Polymerization.The particle sizes were changed with temperature studied by Dynamic Light Scattering(DLS),the surface of particles was studied by Atomic Force Microscopy(AFM).The results indicated that the microgel has the characteristic of temperature sensitive.The particle size change from 342.5nm to 870.4nm with the content of MBA from 2%to 10%,the surfaces of particles and the lower critical solution temperature(LCST) don't change.And the LCST changed from 42℃to 34℃with the content of NVP from 0.0%to 24%,the particles single dispersion is best when the content of NVP is 10%.The results is the microgel particles hybrid with HAP through the chemical bond of O-Ca-O.We obtained the different content of Maleic Anhydride(Mah) ABA block polymers of PVP₂₁₅-P(NVP-co-Mah)n-PVP₂₁₅,PVCLm- P(NVP-co-Mah)p- PVCLm and P (VCL-co-NVP) ₁₀₇- P(NVP-co-Mah)q- P(VCL-co-NVP)₁₀₇ by RAFT.The polymers were dissolved in water and hybrided with HAP.We found the size of hybrid microgel particles related with HAP;the size of particles is changed with the content of HAP,it has the deposition when getting to the same content of polymers.The polymer and the HAP hybrided together by O- Ca- O.The polymer is in the surface of the HAP.ABA polymer hybrided with HAP after reacted with HEMA.We can get shell-core structured temperature sensitive microgel by Precipitation Polymerization.The single dispersion and the temperature sensitive of the HAP hybrid shell-core structured microgel are better than it has no HEMA.The polymer is in the surface of the HAP.