學生：李明真 指導教授：陳澄河 教授 日期：2015/12/15 氧化鋰作為SDC 電解質燒結助劑的可行性和機制

Outline Experimental Results and discussion 1

Outline Experimental 2

Introduction(1/3) 1.Hydroxypropylcellulose (HPC) is a kind of hydroxyl-substituted cellulose derivatives and has been used in pharmaceutical, adhesives, food, cosmetic and controlled drug release. Nowadays, its thermo-sensitive property has caused scientists' interest. 2. The dipole moment of the propylene oxide moieties may be decreased in water and the hydrophobic interaction of HPC is so strong that the phase separation of HPC aqueous solution occurs. HPC (羥丙基纖維素) 3

Introduction(2/3) 3.Interpolymer hydrogen bonding between HPC and PAA led to a dramatic decrease of phase transition .More interestingly, with the help of hydrogen bonding interaction between AA, PAA and HPC, HPC chains dehydrated to form nanocolloids around room temperature and then PAA chains attached on the surface of HPC nanocolloids collapsed to form PAA nanogels, in which HPC acted as a template for the formation of nanogels. 4

Introduction(3/3) 4.Herein, using HPC as a template in the absence of surfactant, we synthesized HPC/PMAA nanogels which were dual-responsive to pH and temperature owing to the interpolymer hydrogen bonding between HPC and PMAA, and the influence of polymerization temperature, crosslinker concentration, and HPC concentration to effect size and size distribution of dual-responsive nanogels were systematically studied. PMAA (聚甲基丙烯酸) 5

Outline Introduction Experimental Results and discussion Conclusions 6

Experimental -Materials Hydroxypropylcellulose (HPC) powders (average Mw = 1.0 × 105 ) Methacrylic acid monomers (MAA, 99%) N , N′-methylenebisacrylamide (BIS, crosslinker, 99%) 7

Experimental -Materials Ammonium persulfate (APS, 99%, initiator) N , N , N′, N′-tetramethylethylenediamine (TEMED) Sodium hydroxide (NaOH) 8

0.1 g crosslinking agent BIS Experimental -Aqueous synthesis of nanogels 1 wt.% HPC (aq) 20g dissolving HPC powder in deionized water under gentle stirring for one week at room temperature 0.3 g MAA 0.1 g crosslinking agent BIS 0.1 g APS dissolved in 79.4 g DI water under stirring for 60 min to make a homogenous solution. HPC nanogels 9

Experimental The HPC/MAA solution 0.05 g TEMED purged with nitrogen for 40 min and heated up to 30 °C ,stabilizing for 20 min. 0.05 g TEMED initiate polymerization and crosslinking to proceed for 60 min Nanogels were dialyzed for 3 days remove the unreacted MAA, BIS, and TEMED deprotonated to pH = 6.5 ± 0.1 by NaOH DLS UV–Vis spectrophotometer FTIR TEM AFM 10

Experimental 11

Outline Introduction Experimental Results and discussion Conclusions 12

Results and discussion 13

Results and discussion 14

Results and discussion 15

Results and discussion 16

Results and discussion 17

Results and discussion PMAA (聚甲基丙烯酸) 18

Results and discussion 19

Outline Introduction Experimental Results and discussion Conclusions 20

Conclusions(1/2) 1.Dual-responsive HPC nanogels have been synthesized using HPC as a template in surfactant-free aqueous media. 2.It was found that the average size of HPC nanogels changed little with increasing polymerization temperature below 26 °C, whereas it greatly increased above 26 °C. 3.When the concentration of HPC was increased from 0.1 to 0.9 wt.%, the diameter of nanogels decreased firstly and then increased. 21

Conclusions(2/2) 4.Besides, an increasing crosslinker BIS concentration led to a reduced size of HPC nanogels, and the nanogels had the narrowest size distribution when its concentration was 0.1 wt.%. It was demonstrated that nanogels were both thermo sensitive and pH sensitive due to the coexistence of HPC and PMAA. 5.This green method to prepare HPC nanogels in aqueous solution without surfactant can effectively prevent organic solvent from polymerization system. Dual-responsive HPC nanogels are promised to be used in the field of drug delivery and other nanobiomaterials. 22

Thank you for your attention