Santoso, Heru (2026) Sintesis Material Poliuretan Self-healing dari Isosianat Trimer Melalui Reaksi Diels-Alder. Doctoral thesis, Institut Teknologi Sepuluh November.
![[thumbnail of 7008212001-Doctoral.pdf]](http://repository.its.ac.id/style/images/fileicons/text.png) |
Text
7008212001-Doctoral.pdf Restricted to Repository staff only Download (5MB) | Request a copy |
Abstract
Pengembangan material poliuretan swasembuh (self-healing polyurethane) berbasis mekanisme kovalen dinamis Diels-Alder (DA) menjadi solusi inovatif untuk meningkatkan masa pakai dan keberlanjutan material struktural. Namun, tantangan utama pada sistem ini adalah menjaga stabilitas mekanik tanpa mengorbankan mobilitas molekuler yang diperlukan bagi proses penyembuhan mandiri. Penelitian ini bertujuan untuk mensintesis dan mengevaluasi performa poliuretan swasembuh dengan memanfaatkan isosianat trimer berbasis hayati (pentamethylene diisocyanate trimer atau PDI trimer) sebagai agen pengikat silang (crosslinker) utama guna membentuk arsitektur jaringan tiga dimensi yang kokoh. Metodologi penelitian ini mencakup sintesis poliuretan cerdas yang difungsionalisasi dengan gugus furan dan maleimida, diikuti dengan analisis komparatif terhadap pengaruh variasi rasio stoikiometri [NCO]/[OH] (1,5 dan 3) serta efektivitas jenis katalis timah, yaitu dibutyltin dilaurate (DBTDL) dan dibutyltin diacetate (DBTDA). Karakterisasi struktur dan pembuktian reversibilitas ikatan dinamis dilakukan menggunakan spektroskopi FTIR, 1H-NMR serta analisis termal DSC. Evaluasi kapabilitas penyembuhan mandiri diukur melalui pemulihan sifat mekanik pasca-kerusakan terkontrol dengan memberikan stimulus termal pada suhu retro-Diels-Alder. Hasil penelitian menunjukkan bahwa penggunaan PDI trimer secara signifikan meningkatkan stabilitas termal dan integritas jaringan polimer. Analisis FTIR, 1H-NMR dan DSC mengonfirmasi keberhasilan reaksi Diels-Alder reversibel pada rentang suhu 120 - 150oC. Katalis DBTDL terbukti memberikan distribusi jaringan yang lebih homogen dan performa mekanik yang lebih unggul dibandingkan DBTDA. Hal tersebut disebabkan oleh stabilitas termal dan kompatibilitas yang lebih baik dalam sistem trimer. Formulasi rasio [NCO]/[OH] = 3 menunjukkan kandungan gel yang lebih tinggi dan entalpi pelelehan (H) yang lebih rendah, yang mengindikasikan pembentukan jaringan yang lebih rapat dan stabil. Kesimpulan utama dari disertasi ini adalah penggunaan PDI trimer mampu mengatasi kontradiksi antara kekuatan mekanik dan kemampuan swasembuh. Temuan penelitian ini menunjukkan bahwa pada rasio [NCO]/[OH] = 3, efisiensi pemulihan mekanik melampaui 100%. Fenomena ini diidentifikasi sebagai hasil sinergi antara penutupan retakan melalui mekanisme Diels-Alder dan penguatan matriks tambahan akibat proses pasca-pemanasan (post-curing) terhadap gugus isosianat sisa. Secara keseluruhan, penelitian ini memberikan kontribusi ilmiah penting dalam pengembangan polimer cerdas berbasis sumber daya terbarukan yang memiliki potensi aplikasi luas pada sektor pelapis industri dan komponen struktural berkelanjutan.
================================================================================================================================
The development of self-healing polyurethane materials based on the Diels-Alder (DA) dynamic covalent mechanism represents an innovative solution for enhancing the service life and sustainability of structural materials. However, a significant challenge in these systems remains the maintenance of mechanical stability without compromising the molecular mobility essential for the autonomous healing process. This research aims to synthesize and evaluate the performance of self-healing polyurethanes by utilizing a bio-based pentamethylene diisocyanate trimer (PDI trimer) as the primary crosslinking agent to construct a robust three-dimensional network architecture. The methodology encompasses the synthesis of smart polyurethanes functionalized with furan and maleimide moieties, followed by a comparative analysis of the effects of varying [NCO]/[OH] stoichiometric ratios (1.5 and 3) and the efficacy of organotin catalysts, specifically dibutyltin dilaurate (DBTDL) and dibutyltin diacetate (DBTDA). Structural characterization and the verification of dynamic bond reversibility were conducted using FTIR spectroscopy, 1H-NMR, and Differential Scanning Calorimetry (DSC) thermal analysis. Self-healing capability was quantified through the recovery of mechanical properties following controlled damage, facilitated by thermal stimuli at retro-Diels-Alder temperatures. The results demonstrate that the application of PDI trimer significantly enhances the thermal stability and integrity of the polymer network. FTIR, 1H-NMR, and DSC analyses confirmed the successful reversible Diels-Alder reaction within a temperature range of 120–150°C. The DBTDL catalyst was proven to yield a more homogeneous network distribution and superior mechanical performance compared to DBTDA, attributed to its enhanced thermal stability and compatibility within the trimer system. Furthermore, the formulation with an [NCO]/[OH] ratio of 3 exhibited a higher gel content and lower melting enthalpy (H), indicating the formation of a denser and more stable crosslinked network. The primary conclusion of this dissertation is that the utilization of PDI trimer effectively overcomes the contradiction between mechanical strength and self-healing capacity. A critical finding reveals that at an [NCO]/[OH] ratio of 3, the mechanical recovery efficiency exceeds 100%. This phenomenon is identified as a synergistic result of crack closure via the Diels-Alder mechanism and additional matrix strengthening due to the thermal post-curing of residual isocyanate groups. Overall, this research provides a significant scientific contribution to the development of bio-based smart polymers with broad application potential in industrial coatings and sustainable structural components.
| Item Type: | Thesis (Doctoral) |
|---|---|
| Uncontrolled Keywords: | Self-healing, poliuretan, PDI trimer, Diels-Alder, rasio stoikiometri, katalis, isosianat bio-based Self-healing, polyurethane, PDI trimer, Diels-Alder, stoichiometric ratio, catalyst, bio-based isocyanate |
| Subjects: | T Technology > TP Chemical technology > TP1140 Polymers T Technology > TP Chemical technology > TP155.7 Chemical processes. |
| Divisions: | Faculty of Industrial Technology and Systems Engineering (INDSYS) > Chemical Engineering > 24001-(S3) PhD Thesis |
| Depositing User: | Heru Santoso |
| Date Deposited: | 02 Feb 2026 04:21 |
| Last Modified: | 02 Feb 2026 04:21 |
| URI: | http://repository.its.ac.id/id/eprint/131563 |
Actions (login required)
 |
View Item |