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"Pada penelitian ini, Ion Imprinted Polymer (IIP) disintesis dengan metode polimerisasi bulk berbasis Ultrasonic Assisted Dispersive untuk ekstraksinya dengan asam galat sebagai monomer fungsional dan logam Cd²⁺ sebagai template. Hasil karakterisasi FTIR dan SEM-EDX menunjukkan keberhasilan terbentuknya produk Cd(II)-IIP serta terbentuknya rongga spesifik dari Cd(II)-IIP. TGA menujukkan tiga dekomposisi termal dari Cd(II)-IIP dan NIP. Uji adsorpsi menunjukkan bahwa perbandingan sintesis yang optimal dihasilkan pada rasio perbandingan ligan:monomer 1:1 dengan kapasitas adsorpsi 159,038 mg/g pada pH 7 dan waktu kontak 90 menit. Persamaan regresi dari Cd(II)-IIP Ultrasonic Assisted Dispersive mengikuti model isoterm Freundlich dengan . Hasil penelitian menunjukkan selektivitas yang baik terhadap interferensi logam Zn(II), Fe(III), Cr(III), Cu(II), dan Pb(II) dengan koefisien selektivitas >1. Penggunaan Cd(II)-IIP memiliki repeatabilitas yang baik dengan nilai CV Horwitz sebesar 1,39% dan %RSD yaitu 1,11%. Kemampuan recovery Cd(II)-IIP diuji dengan menggunakan sampel saluran Mookervart dan didapatkan %recovery sebesar 101,88%, 102,02%, dan 102,16%.

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In this study, Ion Imprinted Polymer (IIP) was synthesized by bulk polymerization method based on Ultrasonic Assisted Dispersive for its extraction with gallic acid as functional monomer and Cd2+ metal as template. The results of FTIR and SEM-EDX characterization showed the successful formation of Cd(II)-IIP products and the formation of specific cavities of Cd(II)-IIP. TGA shows three thermal decompositions of Cd(II)-IIP and NIP. The adsorption test showed that the optimal synthesis ratio was obtained at a 1:1 ligand:monomer ratio with an adsorption capacity of 159.038 mg/g at pH 7 and a contact time of 90 minutes. The regression equation of Cd(II)-IIP Ultrasonic Assisted Dispersive followed the Freundlich isotherm model with R^2=0.9964. The results showed good selectivity against metal interference Zn(II), Fe(III), Cr(III), Cu(II), and Pb(II) with selectivity coefficient >1. The use of Cd(II)-IIP has good repeatability with CV Horwitz value of 1.39% and %RSD of 1.11%. The recovery ability of Cd(II)-IIP was tested using a Mookervart channel sample and obtained %recovery of 101.88%, 102.02%, and 102.16%."

"In this work mixing rule of sanches - lacombe equation of state (SL-Eos) was developed for estimating vapor-liquid equilibria of solvent-polymer systems or solubility of solvent in polymer solutions....."

"Material polimer untuk menyusun hidrogel harus dapat mengembang (swell) dan mempertahankan fraksi air pada strukturnya, namun tidak larut dalam air. Polimer alami memiliki gugus fungsi yang dapat menjadi pusat aktif reaksi dimana dapat dilakukan modifikasi untuk menghasilkan suatu polimer dengan karakteristik yang lebih baik. Kitosan merupakan polimer alami yang memiliki kekuatan struktur yang kurang dibandingkan kemampuan swelling. Sintesis hidrogel kitosan dengan metode full interpenetrating polymer network (IPN) dapat meningkatkan kekuatan struktur melalui ikat silang. Tahap pertama adalah sintesis jaringan polimer kitosan terikat silang asetaldehida. Tahap kedua adalah sintesis jaringan polimer PNVCL terikat silang N, N?-metilenbisakrilamida (MBA) melalui polimerisasi radikal bebas monomer NVCL dengan inisiator amonium persulfat (APS). Variasi waktu, rasio kitosan-PNVCL, konsentrasi agen pengikat silang, dan konsentrasi inisiator dipelajari untuk mengetahui kondisi optimum. Kondisi optimum diperoleh pada reaksi 2 jam dengan rasio kitosan/NVCL 90:10 (b/b %), konsentrasi MBA 0,5%, dan konsentrasi APS 3%. HSA kitosan-PNVCL memberikan rasio swelling 380,66% dan derajat ikat silang 60,85%. Karakterisasi HSA dilakukan dengan spektrofotometer Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), dan X-Ray Diffraction (XRD).

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Polymer material used for hydrogel should have the ability to swell and to keep water molecules in its structure without dissolving in water. Natural polymers has functional groups which can perform as active sites in modification to produce polymer with better characteristic. Chitosan is a natural polymer which has good swelling ability but lack of structural strength. Synthesis of chitosan hydrogel by interpenetrating polymer network (IPN) will increase its strength through crosslinking. In this research, the first step of modification was the synthesis of chitosan polymer network crosslinked by acetaldehyde. The next step was the synthesis of PNVCL polymer network crosslinked by N,N-methylbisacrylamide (MBA) through free radical polymerization of NVCL monomer with ammonium persulfat (APS) as the initiatior. Optimum reaction time, chitosan/PNVCL ratio (w/w %), concentration of crosslinker agent, and concentration of initiator had been observed. The optimum conditions were obtained as followed: 2 hours reaction, the ratio chitosan/PNVCL of 90:10 (w/w %), %-w MBA concentration of 0,5%, and APS concentration of 3%. The swelling ratio of the hydrogel was 380,66% while the crosslinking degree was 60,85%. Fourier transfor infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), and X-Ray diffraction (XRD) were used for the characterization of the hydrogel."

"Telah dilakukan penelitian mengenai Polimer SBR untuk mengetahui pengaruhnya terhadap hotmix menggunakan Aspal Non-lokal (Esso). Agregat yang tercampur dengan komposisi optimum, dipanaskan hingga suhu 150oC lalu dicampurkan dengan Aspal, kemudian diaduk. Saat suhu turun hingga 80oC, Polimer SBR dimasukkan ke dalam hotmix dan diaduk kembali. Setelah itu, dimasukkan ke dalam cetakan dan dilakukan pemadatan 2x75 kali tumbukan hingga dilakukan pengujian Marshall. Hasil pengujian Marshall yang mencampurkan hotmix dengan Polimer SBR dengan komposisi 1% dan 2% variasi 1:0, 1:1, 1:3, dan 1:6, yakni nilai Stabilitas berada antara 200-350 Kg, nilai Kelelehan berada antara 4,8-5,8 mm, VIM berada antara 11-18 %, VMA berada antara 18-24 %, dan nilai MQ berada antara 30-107 Kg/mm. Polimer SBR ini terlihat berpengaruh pada hotmix terhadap peningkatan kelelehan, namun stabilitas justru menurun. Hal ini karena Polimer SBR bersifat merekat, yang akan memberikan kelenturan yang lebih baik.

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This work has been performed to evaluate the influence of SBR Polymer on asphalt hotmix using imported asphalt, so called ESSO asphalt. Using technical standard compositions of aggregates and Esso asphalt were heated separately until 150oC and then mixed together until the homogenity reached. Following this mixtured procedure, this materials were cooled in air until the temperature reached to 80oC and then compacted for Marshall test. The SBR Polymer composition were variated by persentage 1% and 2% and by ration between SBR Polymer and water of 1:0, 1:1, 1:3 and 1:6 were compacted using Proctor standard procedure.

The Mashall test shows the results: stability between 200-350 Kg, flow between 4.8-5.8 mm, VIM between 11-18 %, VMA between 18-24 %, and MQ value between 30-107 Kg/mm. The work concluded that the influence of SBR Polymer addition on Esso asphalt hotmix shows the increasing of the flow but decreases the stability due to the adhesive properties of the SBR polymer and therefore increase the ductility of the asphalt concrete."