This thesis deals synthesis and characterization of hyperbranched polyamidoamine (HPAMAM) particles. We attempted the synthesis of various type of HPAMAM particles via inverse suspension polymerization and O/W/O suspension polymerization. These particles can capture the metal ions in aqueous solution and $CO_2$ in flue gas.
Firstly, we synthesized silica-HPAMAM hybrid particles. The silica particles have approximately 700 nm diameter, and the surface thickness of HPAMAM is about 20-50 nm. These particles have a better removal ions efficiency of $Cu^{2+}$ ion at the high concentration than Dowex commercial resin. These particles are easy to synthesize, and recyclable with simple acid treatment.
Secondly, micro-hydrogel particles fully consisting of HPAMAM were readily synthesized by eco-friendly polyaddition reaction of A2 and B4 type monomers via inverse suspension polymerization. Particles were found to be highly efficient for removing heavy metal ions, such as cadmium, copper, lead, nickel, zinc, and cobalt, from water, $Cu^{2+}$ adsorption capacity recorded high up to 0.17 g/g which is superior to other chelating polymer adsorbents. The superb adsorption capacity comes from good hygroscopic property and high density of amine and amide functional groups without any supporter materials. In addition, easy recycle by controlling pH, successful scale-up, as well as complete removal of metal ions from water throughout the column packed with particles completes a strong candidate of cost-effective adsorbent for water purification.
Thirdly, particles and porous HPAMAM particles were obtained by using silica particles via inverse suspension polymerization. The porous HPAMAM particles have about 50 ~ 300 um diameter, and the pore size is about 800 nm diameter. The HPAMAM particles showed many pores that corresponded to the silica particles. As the amount of silica is increase, the number of pore is increased. It was found that the porous HPAMAM particles have a better $Cu^{2+}$ adsorption rate than normal HPAMAM particles.
Finally, HPAMAM particles with 30 - 300μm-sized were well synthesized via inverse suspension polymerization, despite the experimental scale was increased. In addition, porous HPAMAM particles were obtained via O/W/O suspension polymerization, these pore size were easily controlled by regulating agitation speed of aqueous phase. The $CO_2$ adsorption was measured by using HPAMAM particles packed within acryl column with a continuous flow of $CO_2$. There was a tendency of deteriorating saturation rate with increasing $CO_2$ concentration and decreasing bed height. As monomer ratio reached the value of 2, the decrease in adsorption capacity was observed, and this was because the diffusion of the dissolved $CO_2$ into the polymer particles became challenging as a result of increased cross-link density of the particles. The $CO_2$ adsorption rate of porous HPAMAM particles was 1.25 times higher than normal HPAMAM particles.
이 논문은 hyperbranched polyamidoamine (HPAMAM) 입자의 합성 및 특성을 다루고 있다. 우리는 역 현탁 중합 및 O/W/O 현탁 중합을 통해 다양한 유형의 HPAMAM 입자의 합성을 시도했다. 이 입자는 수용액의 금속 이온과 $CO_2$를 흡착하는 특성을 가지고 있었다.
먼저 실리카-HPAMAM 하이브리드 입자를 합성했다. 실리카 입자는 약 700 nm 직경을 가지며, HPAMAM의 표면 두께는 약 20 - 50 nm이다. 이 입자는 Dowex 상용 수지보다 구리 이온의 제거 효율이 뛰어났다. 이 입자는 합성하기 쉬우며 간단한 산 처리로 재활용 할 수 있었다.
두 번째로, HPAMAM으로 완전히 구성된 하이드로겔 입자를 역상 현탁 중합을 통한 A2 + B4 타입 첨가 반응에 의해 쉽게 합성하였다. 입자는 물에서 카드뮴, 구리, 납, 니켈, 아연 및 코발트와 같은 중금속 이온을 제거하는 데 매우 효율적이며, pH 조절로 쉽게 재활용이 가능하며, 쉽게 대량합성이 가능하였다.
세 번째로, 실리카 입자를 템플레이트로 이용하여 다공성의 고분자 입자를 합성하였다. 다공성의 입자는 약 50-300 um, 기공은 800 nm의 크기를 가지고 있었다. 실리카 입자를 많이 사용할 수록 기공의 숫자는 증가하는 것을 확인하였다. 또한, 다공성의 입자는 구리이온 흡착속도가 더 빠른 것을 보았다.
네 번째로, 약 30-300 um 크기의 HPAMAM 입자를 역상현탁중합으로 합성하였으며, 또한 O/W/O 현탁중합으로 다공성의 HPAMAM 입자를 합성하였다. HPAMAM 입자를 채워 넣은 아크릴 컬럼으로 이산화탄소 흡착실험을 진행한 결과 다공성의 입자가 흡착속도가 약 1.25배 더 빠른 것을 확인하였다.