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"Kopolimer blok responsif pH dan temperatur poli(N-isopropilakrilamida)-blok-poli(2- (dimetilamino)etil metakrilat) (PNIPAM-b-PDMAEMA) disintesis menggunakan polimerisasi reversible addition-fragmentation chain transfer (RAFT) dengan variasi panjang rantai blok PDMAEMA, untuk mengetahui pengaruhnya terhadap temperatur transisi fasa (Tc). Karakterisasi menggunakan instrumen proton nuclear magnetic resonance (1H-NMR) dan fourier transform infrared (FTIR) menandakan produk berhasil terbentuk, didapatkan kopolimer blok PNIPAM21-b-PDMAEMA2 dan PNIPAM21-b-PDMAEMA7. Analisis makro-CTA PNIPAM menggunakan instrumen gel permeation chromatography (GPC) menunjukkan Mn dan PDI sebesar 3475 g/mol dan 1,15 serta dihasilkan distribusi berat molekul yang sempit. Perilaku responsif pH dan temperatur kopolimer blok diamati dalam larutan buffer fosfat pada variasi pH dan temperatur menggunakan instrumen spektrofotometer UV-Visible, hasil menunjukkan gugus ujung karboksil yang bersifat hidrofilik dan gugus ujung dodesil yang bersifat hidrofobik turut serta memberikan pengaruh terhadap Tc yang dihasilkan. Terjadi tren peningkatan Tc saat pH meningkat dari pH 5 ke pH 7,4 sementara dihasilkan Tc yang konstan pada pH 7,4 dan 9 akibat pengaruh blok PNIPAM dan PDMAEMA yang responsif pH. Pengujian menggunakan particle size analyzer (PSA) pada kopolimer blok PNIPAM21-b-PDMAEMA2 pH 5 dan 9 menunjukkan terjadi peningkatan diameter partikel seiring meningkatnya suhu. Kopolimer blok PNIPAM21-b-PDMAEMA7 menunjukkan responsivitas terbaik pada pH 5 dengan Tc 42 °C berpotensi untuk dimanfaatkan dalam bidang pengobatan penyakit kanker.......Stimuli responsive block copolymers of poly(N-isopropylacrylamide)-block-poly(2- dimethylamino)ethyl methacrylate) (PNIPAM-b-PDMAEMA) were successfully synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization by varying the chain length of the second block (PDMAEMA), and studied its effect on the phase transition temperature (Tc) as well as pH- and thermo- responsive behavior. Characterization using proton nuclear magnetic resonance (1H- NMR) and fourier transform infrared (FTIR) instruments indicate the product of block copolymers PNIPAM21-b-PDMAEMA2 and PNIPAM21-b-PDMAEMA7 were successfully formed. Analysis using gel permeation chromatography (GPC) showed Mn 3475 g/mol and PDI 1.15 corresponding to PNIPAM macro-CTA with narrow molecular weight distribution. Thermo- and pH-responsive behavior of block copolymers was investigated in phosphate buffer of varying pH and temperature using UV-Visible spectrophotometer. The results showed that the hydrophilic carboxyl end group and the hydrophobic dodecyl end group had an effect on the resulting Tc. There was an increasing trend of Tc when pH increased from pH 5 to pH 7.4 while Tc was constant at pH 7.4 and 9 due to the effect of pH-dependent PNIPAM and PDMAEMA blocks. Diameter particle of block copolymers PNIPAM21-b-PDMAEMA2 in pH 5 and 9 increased along with heating based on particle size analyzer (PSA) results. Moreover, block copolymers PNIPAM21-b-PDMAEMA7 with Tc 42 °C at pH 5, has the potential to be used in cancer treatment."

"Cellulose having a medium-responsive function were synthesized by photografting of methacrylic acid (MAA) on regenerated cellulose film (thickness = 20 µm) at 60°C using mixed solvent consisting of water and organic solvents such as acetone and methanol. Xanthone was used as photoinitiator by coating on the film surfaces. A maximum percentage of grafting was observed at a certain concentration of organic solvent. MAA-grafted cellulose films produced showing homogeneous distribution of grafted chains, which was examined by scanning electron microscopy. The modified films also exhibit medium responsive character, it shrinks in acidic and swells in basic solution. Moreover, the grafted film exhibited the ability to absorb copper ion, which was not influenced by the solvent used in grafting processes."

"Pada penelitian ini dilakukan sintesis polimer hidrogel poli(N-isopropilakrilamida-ko-2-dimetilaminoetil metakrilat) (P(NIPAM-ko-DMAEMA)) yang mempunyai sifat responsif temperatur dan pH dengan menggunakan mekanisme polimerasi radikal bebas menggunakan inisiator ammonium persulfat (APS) dan agen pengikat silang N,N’-metilenbisakrilamida (MBA). Hidrogel P(NIPAM-ko-DMAEMA) dilakukan karakterisasi menggunakan fourier transform infrared (FTIR) dan didapatkan hilangnya puncak pada Csp2 pada gugus vinil monomer yang menandakan proses polimerisasi berhasil. Pada uji persen gel didapatkan bahwa semakin tinggi komposisi DMAEMA, persen gel akan semakin kecil berbanding terbalik dengan hal tersebut rasio swelling hidrogel akan semakin besar.  Pada uji swelling di berbagai temperatur didapatkan bahwa semakin tinggi temperatur, rasio swelling akan semakin kecil. Pada uji swelling di berbagai pH didapatkan bahwa semakin tinggi pH, rasio swelling akan semakin kecil. Hasil uji swelling di berbagai temperatur dan pH menunjukkan bahwa rasio swelling terbesar dimiliki oleh hidrogel P(NIPAM-ko-DMAEMA) dengan komposisi monomer NIPAM 30 mol% dan monomer DMAEMA 70 mol% serta komposisi agen pengikat silang MBA 2 mol%. Didapatkan bahwa hidrogel P(NIPAM30-ko-DMAEMA70) memiliki potensi sebagai penghantar bahan aktif dengan besar persen enkapsulasi metformin-HCl sebesar 65,304% w/w dan pelepasan sebesar 26,83% dalam buffer pH 6,8 pada temperatur 37.......In this research, poly(N-isopropylacrylamide-co­-2-dimethylaminoethyl methacrylate) (P(NIPAM-co-DMAEMA)) hydrogels with temperature- and pH- responsive properties were synthesized by the mechanism of free-radical polymerization, using ammonium persulfate (APS) as initiator and N,N’-methylenebisacrylamide (MBA) as crosslinking agent. The P(NIPAM-co­-DMAEMA) hydrogels were characterized by using the Fourier Transform Infrared (FTIR) and resulting in the non appearence of Csp2 peak of the monomer vinyl structure that indicates the polymerization process success. The gel percentage tests concluded that the higher the DMAEMA composition, the gel percentage will be lower, in contrast with that, the swelling ration of the hydrogel will be higher. The swelling test on several scales of temperature identified that the higher the temperature is, the lower the swelling ratio will be. Correspondingly, the swelling test with various pHs exhibit that the higher the pH is, the lower the swelling ratio will be. It was discovered that the swelling tests on various temperatures and pHs result in the highest swelling ratio on P(NIPAM-co-DMAEMA) hydrogel with the composition of 30 mol% of NIPAM monomer, 70 mol% of DMAEMA, and 2 mol% of crosslinking agent. The P(NIPAM30-co-DMAEMA70) hydrogel is potential as a carrier to encapsulate 65.304% w/w metformin HCl with 26.83% release in buffer pH 6.8 at 37°C."

"Serangkaian nanogel responsif pH dan temperatur poli(N-vinilkaprolaktam-ko-2-(dimetilamino)etil metakrilat) (P(NVCL-ko-DMAEMA)) telah disintesis melalui polimerisasi emulsi radikal bebas. Dalam proses sintesis, komposisi monomer N-vinilkaprolaktam (NVCL) dan 2-(dimetilamino)etil metakrilat (DMAEMA) serta konsentrasi agen pengikat silang N,N’-metilenbisakrilamida (MBA) dibuat bervariasi yang ditujukan untuk menginvestigasi pengaruhnya terhadap responsivitas pada perubahan pH dan temperatur. Berdasarkan hasil karakterisasi FTIR dan 1H-NMR, ditunjukkan bahwa reaksi polimerisasi yang terjadi berhasil membentuk nanogel. Karakterisasi menggunakan spektrofotomer UV-Vis terhadap nanogel hasil sintesis menunjukkan bahwa setiap nanogel bersifat responsif terhadap pH dan temperatur dimana diketahui bahwa nanogel P(NVCL75-ko-DMAEMA25) 8% MBA yang memiliki temperatur transisi fasa (Tc) sebesar 50°C pada pH 7,4 menunjukkan responsivitas yang paling signifikan dibanding nanogel dengan variasi komposisi monomer dan variasi konsentrasi agen pengikat silang lainnya. Berdasarkan karakterisasi PSA, ditunjukkan bahwa ukuran partikel nanogel P(NVCL75-ko-DMAEMA25) 8% MBA meningkat seiring dengan meningkatnya temperatur. Hasil penelitian juga menunjukkan bahwa terdapat pengaruh komposisi monomer nanogel terhadap nilai Tc dimana Tc nanogel meningkat seiring dengan bertambahnya komposisi monomer DMAEMA dalam struktur nanogel. Sebaliknya, seiring dengan meningkatnya konsentrasi MBA dalam nanogel P(NVCL-ko-DMAEMA), diamati Tc nanogel menurun. Selain itu, nanogel yang dihasilkan dengan komponen polibasa berupa PDMAEMA memiliki nilai Tc yang cenderung rendah pada pH tinggi atau lingkungan basa.......A series of pH and temperature-responsive nanogels poly(N-vinylcaprolactam-co-2-(dimethylamino)ethyl methacrylate) (P(NVCL-co-DMAEMA)) was synthesized by free-radical emulsion polymerization. In the synthesis process, the composition of the monomers N-vinylcaprolactam (NVCL) and 2-(dimethylamino)ethyl methacrylate (DMAEMA), as well as the concentration of the crosslinking agent N,N'-methylenebisacrylamide (MBA), were varied to investigate their effect on responsiveness to changes in pH and temperature. Based on the results of FTIR and 1H-NMR characterization, it was shown that the polymerization reaction that occurred succeeded in forming nanogels. The UV-Vis spectrophotometer characterization of the synthesized nanogels showed that each nanogel was responsive to pH and temperature in which P(NVCL75-co-DMAEMA25) 8% MBA nanogel had a phase transition temperature (Tc) of 50°C at pH 7.4 and showed the most significant responsiveness compared to another nanogels with variations in monomer composition and variations in crosslinker concentrations. Based on PSA characterization, it was shown that the particle size of the P(NVCL75-co-DMAEMA25) 8% MBA nanogel increased with the increase of temperature. The results also showed that there was an effect of the composition of the nanogel monomer on the Tc value where the Tc of the nanogel increased with the increase of the composition of the DMAEMA monomer in the nanogel. On the other hand, as the concentration of MBA in the P(NVCL-co-DMAEMA) nanogel increased, it was observed that the Tc of the nanogel decreased. In addition, the resulting nanogel with polybasic components in the form of PDMAEMA has a Tc value that tends to be low in high pH or alkaline environments."