Tài liệu Study on synthesis and curing acrylated black seed oil

MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY INSTITUTE FOR TROPICAL TECHNOLOGY ----------***---------- DAM XUAN THANG STUDY ON SYNTHESIS AND CURING acrylated black seed oil MAYJOR: organic chemitry code : 62 44 01 14 Summary of doctoral thesis Ha Noi - 2014 The work has completed at Institute of Tropical Technology – Vietnam Academy of Science and Technology Supervisor 1: Assoc.Pro.Dr. Le Xuan Hien Supervisor 2: Assoc.Pro.Dr. Nguyen Thi Viet Trieu Referee 1: Assoc.Pro.Dr. Tran Thi Nhu Mai, Vietnam National University, Hanoi - University of Science Referee 2: Assoc.Pro.Dr. Le Thi Anh Dao, Hanoi National University of Education Referee 3: Assoc.Pro.Dr.Bach Trong Phuc, Hanoi University of Science and Technology The thesis will be defended in front of doctoral thesis judgement, held at Institute for Tropical Technology - Vietnam Academy of Science and Technology at 9 AM, 10th November, 2014. The thesis can be found at: - Library of Institute for Tropical Technology. - Vietnam National Library. - Website of Institute for Tropical Technology: http://itt.ac.vn 1 INTRODUCTION 1. The urgency of the thesis Metal and non-metal materials play an important role in production and the lives. Degrading metal and non-metal materials by environmental conditions are enormous causes economic damage. Vietnam stays in tropical zone and has long coastline, approximately 3000km and thus speed of corrosion in Vietnam is near five-times higher than other climate areas. Damages of corrosion, degradation and ageing metal materials combining with costs of protection materials in Vietnam are estimated round one billion USD per year. Depending on properties of materials and factor causes corrosion and degradation, there are many methods against corrosion and degradation materials such as: electrochemical, inhibitor, protective coating… Today, protected material, especially UV-curing paints becomes more popular. Besides, the demand of preparation of high quality and friendly environmental materials significantly increase due to global climate change and pollution becoming serious. One of the protected and high quality decorative materials having attracted the attention of researchers and producers is materials containing acrylate groups because these materials have advantaged features such as weather resistance, chemical resistance, abrasion resistance and good biological interactions. Currently, protective and decorative materials based on acrylated vegetable oil have been interested because it combines the advantages of acrylate compounds and vegetable oil as well as taking advantage of natural resources: available, inexpensive and environmentally friendly. Research, development and application materials based on acrylated vegetable oils not only help to overcome some disadvantages of low molecular weight acrylate compounds such as dermatitis, skin allergies, but also contribute in the development of advanced processing methods. Vegetable oils are abundant and renewable material. Particularly, vegetable oils containing high chemical activity epoxy groups (synthetic or natural) can be used directly or modified by acrylated to preparation higher quality and diverse products. The demand for high quality protected and decorative materials is gigantic in Vietnam which is in harsh climate zone. With abundant vegetable oil, especially black seed oil which contains natural epoxy groups in Northwest of Vietnam has been little attraction in research and thus researching protective and decorative coating based on generally acrylated vegetable oil, particularly acrylated black seed oil, is essential. Thesis: “Study on synthesis and curing acrylated black seed oil” has been done to solve above problems. 2. The objectives of the thesis - Determine optimal condition for acrylating black seed oil and crosslinking of photo-systems based on acrylated black seed oil produces good quality films. - Evaluate the possibility of using acrylated black seed oil to produce high quality protective and decorative materials. 3. Significance - Identified some rules and relationships of the chemical nature of the agent, reaction conditions and kinetics, structure and nature of the acrylated black seed oil and photocrosslinking systems based on acrylated black seed oil. 2 - Evaluation and selection of conditions for acrylated black seed oil reaction and photocrosslinking of systems based on acrylated black seed oil to create protective, decorative coatings meets some practical demands. - Exploitation and efficient using vegetable oil. 4. Structure of the thesis Thesis includes three parts: Main content (139 pages); References (11 pages); Appendix (57 pages): Namely: - Main content: Introduction (3 pages); Chapter 1. Literature review (37 pages); Chapter 2: Experimental (8 pages); Chapter 3: Results and discussion (87 pages); Conclusion (2 pages); the list of author’s research (1 page). - References: 111 documentations consist of: 28 Vietnamese documentations; 72 English documentations and 1 Russian documentation. - Appendix: IR, UV-Vis, spectroscopies. 1 HNMR, 13 CNMR; DEPT; HSQC; HMBC and MS Chapter 1. BACKGROUND OVERVIEWS The literature presents an overview of the history of research, development, using the compounds containing acrylate and protective, decorative materials in the world and Vietnam. The latest data on the production and consumption of organic protected, decorative materials shows the distribution of the quantity, types and values as well as their properties are diverse and increasing in recent years. Due to the increasing demand for quality and environmental materials, the trends of research and development of protective and decorative materials not only changes in the structure and categories but also use a variety of modern methods such as: electrophoretic paint, photo-crosslinking, ... Protective, decorative materials based on acrylated vegetable oil usually have good mechanical properties by combining the advantages of flexible vegetable oil and the hard acrylic component have attracted the attention of researchers, producers in the world and domestic. The situation of synthesis, manufacture and application of acrylated vegetable oil is fully updated. The analysis of the synthesis, properties and abilities crosslinking of acrylated vegetable oil showed the ability of denatured as well as the properties of the production. Synthesized and analyzed the results of researches, application follow trend of preparation protective and decorative materials based on acrylated vegetable oil. Chapter 2. EXPERIMENTAL 2.1. Materials Black seed oil in Muong Ang, Tuan Giao (Dien Bien) and Thuan Chau (Son La) containing quantity of epoxy groups from 0.87 mol epoxy/mol oil đến 2.36 mol epoxy/mol oil was expeller pressed or extracted in Department of Rubber and Natural resins materials, Institute of Tropical technology. Monomer acrylate Hexanediol Diacrylate (HDDA); Bisphenol A diglycidyl ether dimetacrylate (DGEDM); Bisphenol A diglycidyl ether diacrylate (DGEDA); Mixture monomer and oligomer acrylate H4.12.2 including DGEDM and HDDA with weigh ratio: 25/15; Irgacure 184; Solvents and other pure chemicals: acid acrylic; acid metacrylic, toluene, acetone, ether petro; chloroform… 3 2.2 Isolation black seed oil Fresh black fruit was purchased in Muong Ang, Tuan Giao (Dien Bien) and Thuan Chau (Son La). Fresh fruit was peeled soft coat by hand, and then it was dried or dried at 500C in an oven which was followed by hard coat was smashed by hammer and peeled by hand. Black kernels obtained. 2.3. Acrylated black seed oil by acid acrylic or acid metacrylic Black seed oil was dissolved in toluene with concentration 50% in three-neck flask. Acid acrylic or metacrylic was added with ratio (mol) acrylic/epoxy = 20/1. The solution was stirred and kept at 35, 60 or 80oC. Sample, which was taken after certain time, was neutralized by Na2CO3 5%, and then the organic layer was isolated by separatory funnel and washed by distill water, dried at ambient in vacuum oven. 2.4. Preparation of sample - The sample was prepared by mixing the components. - Films were cast either on a KBr crystal for infrared spectroscopy analysis with 20 m thickness, or on a glass plate for hardness measurements, or on steel and copper plates for determination of other physico-mechanical properties with 30 m thickness. 2.5. Characteristic analysis - Chemical and physical chemistry analysis: The titration; Elemental analysis (EA 1112, USA); IR-analysis (NEXUS 670, USA); UV-Vis analysis (CINTRA 40, GBC, USA); Analysis of nuclear magnetic resonance (Avance 500, Brucker, Germany); MS analysis (Waters-API-ESI, USA). - Determination of the physico-mechanical properties: Gel fraction and the swelling degree; hardness (according standard PERSOZ (NFT 30 – 016)); Resistance impact (according standard ISO 6272); Flexibility (according standard ГOCT 6806-03); Pencil hardness (according standard ASTM D3363-05); Adhesion (according standard ISO 2409). Chapter 3. RESULTS AND DISCUSSIONS 3.1. Study on black seed oil 3.1.1. Study on composition and structure of black seed oil  Acid index Identified acid index of new separation black seed oil by chemical titration was 3.27 mg KOH/g  Epoxy group content Determining epoxy group content by titration methods based on color indicator and voltage measurements showed that the epoxy group content of black seed oil changed over time, venue procurement from about 0.87 to 2.36 moles of epoxy/moles of oil.  Elemental analysis According the results of elemental analysis, the black seed oil contained 14.96% oxygen.  Analysis IR, UV-Vis, NMR spectra. 4 IR, UV-Vis, NMR spectra of black seed oil have very similar spectral shape Vernonia oil. The absorption, resonance signals characteristic of the groups of atoms in black seed oil on the types of spectra studied are presented in Table 3.1 Table 3.1. The absorption, resonance signals characteristic of the groups of atoms in black seed oil on the types of spectra studied Analysis IR Wave (cm-1) 3470 1163 3008 1654 2926 1378 2926; 2855 1461 721 1745 1237; 1101 1725 1260 851 824 Characteristic Absorption UV-Vis (nm) 1 HNMR (ppm) Functional group Valence fluctuation of O-H with H-bond Valence fluctuation of C-O in alcohol Valence fluctuation of C-H olefin. Valence fluctuation of double bond in CIS Valence fluctuation non-symmetry of CH in -CH3 Symmetric deformed oscillator of C-H in -CH3 Valence fluctuation Symmetry and nonsymmetry CH trong nhóm -CH2Non-symmetric deformed oscillator of CH trong -CH2Pendulum oscillation of -CH2Valence fluctuation of carbonyl in ester. 225nm: transformation Valence fluctuation of C-O in ester. n →π* in ester Valence fluctuation of general carbonyl 273nm: transformation n →π* in general carbonyl Valence fluctuation non-symmetry of C – O in epoxy ring Valence fluctuation non-symmetry of epoxy. Deformed oscillator of epoxy. - Hydroxyl 5,30 - 5,53 (-CH=CH-) 0,87 - 0,92 (CH3-) 1,25 - 1,61 (-CH2-) - (-COO-) - General carbonyl Epoxy group 2,76 - 2,93 The analysis results obtained showed that black seed oil has similar functional group like ester, epoxy, double bone olefin and molecular weight Vernonia oil. As a result, the black seed oil has similar structure Vernonia oil with follow structural formula: 5 Thesis will analyses the NMR spectra of black seed oil. - 1H-NMR spectra of black seed oil Table 3.2. Comparison of data 1H-NMR spectra of black seed oil and Vernonia Type proton Proton hydroxyl (OH) Proton olefin (CH=CH) Proton glyxerin (CH) Proton glyxerin (CH2) Proton epoxy (OCH) Methylene (CH2-CH=CH-CH2) Methylene (CH2)n Methyl (CH3) Chemical shifts (δ, ppm) Black seed oil Vernonia oil 5,30 - 5,53 5,22 - 5,56 5,25 5,22 -5,56 4,12 - 4,31 4,02 - 4,34 2,76 - 2,93 2,71 - 2,98 2,05 – 2,40 1,94- 2,42 1,25 – 1,61 1,18 - 1,68 0,87 – 0,92 0,81 - 0.91 1 H-NMR, formula, the value of situation and results of analysis H-NMR of black seed oil was illustrated in Fig 3.1 and table 3.3. Fig. 3.1. 1H-NMR spectra of black seed oil Table 3.3. Chemical shifts in the H-NMR spectra of proton of black seed oil Proton Proton Chemical shifts ( , ppm) 9 5,53 (t) B Chemical shifts ( , ppm) 4,12 (m, 2H) 4,31 (m, 2H) 5,25 (t, 1H) 10 1 - 11 2 3 4 5 6 7 8 2,20 (m) 1,61 (d) 1,25 - 1,35 (complex) 1,25 - 1,35 (complex) 1,25 - 1,35 (complex) 1,25 - 1,35 (complex) 2,05 (m) 12 13 14 15 16 17 18 5,30 (t) 2,20 (m) 2,40 (m) 2,93 (t, 3H) 2,76 (t, 3H) 1,52 (m) 1,25 - 1,35 (complex) 1,25 - 1,35 (complex) 1,25 - 1,35 (complex) 0,87 - 0,92 (complex) A G 6 - 13C-NMR and DEPT spectra of black seed oil. Table 3.4. Comparison 13C-NMR between black seed oil and Vernonia oil. Type of carbon Carbon carbonyl (C=O) Carbon olefin (CH=CH) Carbon glycerin (CH) Carbon glycerin (CH2) Carbon epoxy (OCH) Carbon methylene (CH2)n Carbon methyl (CH3) Chemical shift (δ, ppm) Black seed oil Vernonia oil 173,21 173,27 123,94 - 132,58 123,86 - 132,53 68,93 68,88 62,08 62,01 - 64,90 56,54 - 57,20 56,41 - 57,16 24,78 - 34,14 22,55 - 33,88 14,01 13,96 The results of analysis 13C-NMR spectra of black seed oil were presented in table 3.5 Table 3.5. Chemical shifts in the 13C-NMR of the carbons in black seed oil Carbon A B 1 2 3 4 5 6 7 8  Chemical shift ( , ppm) 62,08 68,93 173,21 34,14 24,80 28,99 29,06 29,28 29,31 25,61 Carbon 9 10 11 12 13 14 15 16 17 18 Chemical shift ( , ppm) 132,58 123,94 26,22 57,20 56,54 27,14 27,38 31,88 24,78 14,01 Analysis MS spectra of black seed oil MS high resolution spectra of black seed oil had a peak at m/z = 927 corresponding black seed oil contenting epoxy group content 3.0 moles epoxy/mole oil and 3 double bond/mole oil. According results of chemical analysis, elemental, physical-chemistry and comparison structural data of Vernonia oil or epoxidized soya, thesis proposed that the structure of black seed oil as follow: Black seed oil has 3 epoxy groups and 3 double bonds in their molecular. It has feature as Vernonia oil or epoxidized soya which is using directly or denaturing (acrylation, 7 hydroxylation…), as a stabilizer for chlorinated polymers, reactive diluent in the system and varnish, paint non-solvent, in the photo-curing composite… 3.1.2. Study on change of black seed oil over harvest, storage Based on titration method, spectral analysis has watched transformation of functional group, especially epoxy group in black seed oil depending on time of harvest and storage. IR and UV spectra of black seed oil in the process storage were illustrated in Fig. 3.2 and 3.3. A-Abs m t đô quang 150 140 (d) 130 (c) (%) Transmittance (%) Truy nnqua (%) Truy qua 120 110 90 (b) b 80 70 825.44 851.08 1098.72 1378.83 1239.66 723.46 1654.93 1165.05 10 1463.85 20 2925.89 30 1746.41 40 (a) 2854.74 50 3008.26 60 3470.57 %Transmittance 100 a c 0 4000 3000 2000 1000 Wavenumbers (cm-1) -1 Số Sô ssóng ng (cm cm-1 ) Wavenumber (cm-1 ) Fig 3.2. IR spectra of black seed oil pressed from seed of: fresh (a); after 4 months storage (b), after 1 year storage (c) and after 2 years storage (d). Fig 3.3. UV spectra of black seed oil pressed from seed of: fresh (a); after 4 months storage (b), after 1 year storage (c). According the results of analysis IR, UV spectra and titration, the epoxy and hydroxyl groups of black seed oil had transformed significantly in process of storage oil and seed. Therefore, obtaining quality black seed oil requires suitable process of extraction, separation and storage. There are several conclusions from the results of study on structure and transformation black seed oil over time of harvest or storage:  Based on the results of chemical titration, elemental analysis and analysis IR, UV, NMR, MS had determined the functional group namely ester, epoxy, double bond in molecular as well as mass of molecular of black seed oil which is a triglyceride oil having similar structure Vernonia oil.  According the results of change black seed oil over time storage, epoxy group content decreased over time storage. Therefore, in the fact, we may obtain black seed oil by extraction or mechanical press with epoxy group content from 0.87 to 2.36 moles epoxy/mole oil. 3.2. Study on acrylated black seed oil reaction 3.2.1. Study on IR spectra of black seed oil before and after acrylation IR spectra and the result of analysis IR spectra of black seed oil before and after 60 hours acrylation by acid acrylic were presented in Fig. 3.4 and table 3.6. As can be seen from table 3.6, in the process of acrylation, intensity of absorption characteristic valence fluctuation of C-H at 2927 cm, 2855 cm was almost unchanged. Absorption at 3467 cm characteristic valence fluctuation of hydroxyl, at 1729 cm of carbonyl increased. Absorptions at 1636, 1619, 987 and 810 cm-1 characteristic valence fluctuation, 8 deformed oscillator of double bond acrylate dramatically grew and absorptions at 851, 825 cm-1 charateristic of epoxy group significantly after 60 hours reaction. Therefore, absorption at 2927 characteristic of C-H alkane has been selected as the internal standard to examine the change of the content of the functional group during the process of acrylated black seed oil. 85 (a) 65 60 (b) 55 5 810.96 1060.31 10 1410.54 15 2927.91 20 1729.76 25 2854.14 30 1636.16 35 1250.04 1619.92 40 986.97 45 1096.69 50 3467.86 %Transmittance (%) Transmittance Truy n qua (%) 70 851.64 1654.70 75 825.70 80 0 4000 3000 2000 1000 Wavenumbers (cm-1) Sô s ng (cm-1(cm ) -1 ) Wavenumber Fig. 3.4. IR spectra of black seed oil before (a) and after 60 hours acrylation by acid acrylic at 60oC Table 3.6. Characteristic absorption in the IR spectra of black seed oil before, after acrylation. and transformation of them in the process. Wave number (cm-1) 3467 2927 2854 1729 1636 1619 Black seed oil Characteristic Before Valence fluctuation of Hydroxyl + Symmetric and non-symmetric valence + fluctuation of C-H alkane Valence fluctuation of carbonyl + Valence fluctuation of double bond of acrylate Deformed oscillator of double bond of 1410 acrylate Valence fluctuation of C-O in epoxy 1250 + ring Symmetric valence fluctuation and 851, 825 + deformed oscillator of epoxy group 810 Deformed oscillator of double bond Note: (+)absorption, (-) non-absorption,  Increase,  decrease After Change +  + → +  +  +  -  -  +  3.2.2. The change of functional group in the process of acrylated black seed oil The fig 3.5. showed the change of functional group content in the process of reaction of acrylated black seed oil by acid acrylic at 60oC. As is showed in fig 3.5, the epoxy group content sharply fell and the content of acrylate group, hydroxyl, carbonyl dramatically increased in 36 hours reaction, before the change of functional groups saw slow convert and almost unchanged after 60 hours. 9 0.20 D X /D 2927 D 825 /D 2927 1729 cm 1.0 -1 0.9 3467 cm-1 0.16 -1 1410 cm 0.8 0.12 0.08 cacbonyl : ● hydroxyl : * acrylat : ▲ epoxy : ♦ 0.7 0.6 0.04 825 0.5 cm-1 0.00 0.4 0 10 20 30 40 50 Thời gian phản ứng (giờ ) 60 70 Time reaction (hour) Fig 3.5. The change of functional group in the process of acrylated black seed oil at 60oC. 3.2.3. Influence of several factors on acrylated black seed oil reaction. 3.2.3.1. Influence of temperature on acrylated black seed oil reaction  The change of functional group in the process of acrylated black seed oil Acrylated black seed oil was studied at 35, 60 and 80oC. At 80oC, acrylated black seed oil initially occured rapidly but the reaction was gel after 3.5 hours. The change of content of epoxy, hydroxyl and acrylate in the acrylated black seed oil at 35, 60 C was presented in the fig 3.6 and 3.7. o 0.20 D825 /D 2927 D X /D nh m hydroxyl: 2927 0.16 D825 /D2927 DX /D 2927 0.20 ▲ 0.16 3467 cm 0.16 nh m acrylat 0.12 1410 cm nh m epoxy 0.12 ● : 3467 cm -1 0.08 0.08 0.04 0.04 1410 cm -1 825 cm 30 40 50 ▲ nh m acrylat : ♦ nh m epoxy : ● 0.08 0.04 -1 0.00 20 nh m hydroxyl: 0.04 0.00 10 -1 0.12 0.08 0 -1 0.12 ♦ : 0.16 60 70 Thời gian phản ứng (giờ) Time reaction (hour) Fig.3.6. The change of content of epoxy, hydroxyl and acrylate in the acrylated black seed oil at 35oC 825 cm -1 0.00 0.00 0 10 20 30 40 50 60 70 Thời gian phản ứng (giờ) Time reaction (hour) Fig 3.7. The change of content of epoxy, hydroxyl and acrylate in the acrylated black seed oil at 60oC As is shown from Fig 3.6 and 3.7, reaction of acrylated black seed oil at 35oC obtained lower efficency than acrylated black seed oil at 60oC and thus not studying acrylated black seed oil at lower temperature. According the above results, determined the optimal condition of acrylated black seed oil reaction being temperature at 60oC and time reaction 60 hours for further studies. 3.2.3.2. Study on influence of epoxy group content in black seed oil on acrylation Fig 3.8 presented the change of content of epoxy group and acrylate group in acrylated black seed oil with variety oil containing epoxy group content: 2.2; 1.8; 1.2 and 0.87 moles epoxy/mole oil. 10 D825 / D2927 D1410 / D2927 D825 / D2927 0.16 DHCĐ-2,2E 0.16 0.16 0.12 0.12 D1410 / D 2927 0.12 0.10 DHCĐ-1,8E 0.12 0.08 DHCĐ-1,2E 0.08 0.08 0.08 0.04 0.04 0.04 0.06 0.04 0.02 0.00 0.00 0 10 20 30 40 50 60 70 Thời gian phản ứng (giờ ) Time reaction (hour) Fig 3.8. the change of content of epoxy and acrylate group in acrylated black seed oil with variety oil containing different epoxy group content at 60oC 0.00 0.00 0 10 20 30 40 50 60 70 Thời gian phản ứng (giờ) Time reaction (hour) Fig 3.9. The change of content of epoxy and acrylate group of black seed oil acrylated by acid acrylic (♦)and metacrylic (●)at 60oC As is shown by fig 3.8, the epoxy group of all black seed oil fully converted, the number of acrylate group attaching oil chain reached from 83.33 to 95.45% after 60 hours reaction. Due to reaction of acrylated black seed oil occurred follow 2 stages: in the first stage, opening the ring of epoxy group with high speed and completely due to proton having small size easily protonated and opened the ring of epoxy group. In the next stage, attachment of the acylate group in oil chain experimenced slower speed and efficiency than the previous stage. 3.2.3.3. Influence of substituents on the acrylated black seed oil reaction Fig 3.9 shows the change of content of epoxy and acrylate group of black seed oil containing epoxy group content 1.8 moles epoxy/mole oil acrylated by acid acrylic and acid metacrylic at 60oC. The results of the study, again confirming acrylate chemical reaction mechanism occurs in two stages: first stage was that ring of epoxy group opened by proton and acrylate groups attached to the oil chain in the next stage. Thus, the speed of acrylated black seed oil has no diffirence between acid acrylic and acid metacrylic. These results have similar previous study of Victoria Kolot and her colleages when they studied acrylated Vernonia oil. There are several conclusions from the results of study on acrylated black seed oil by acid acrylic or acid metacrylic:  According the study on IR of black seed oil before and after acrylation, selected absorption at 2927cm-1 characteristic C-H alkane as internal standard to examine the change of content of hydroxyl at 3467 cm-1, carbonyl at 1730 cm-1, acrylate at 1410 cm-1, and epoxy at 825 cm-1 in the reaction. The results were that the content of hydroxyl, carbonyl, and acrylate significantly increased, but the epoxy group content fell substantially.  The optimal condition of acrylated black seed oil: temperature 60oC; the mass ratio black seed oil/toluene = 1/1; the mole ratio acid acrylic or acid metacrylic/epoxy = 20/1; time reaction was 60 hours. The higher content of epoxy makes reactive speed faster and reaction efficient.  Black seed oil containing acrylate and metacrylate synthesized can solve well in toluene, HDDA and having good interoperability with photo initator and thus using in photo curing system. 11 3.3. Determine structure of acrylated black seed oil 3.3.1. IR spectra of acrylated black seed oil Study on the IR spectra of black seed oil before and after acrylated showed that the absorption characteristic of double bond acrylate appeared and the absorption characteristic of epoxy group disappear after acrylation (fig 3.4 and table 3.6). This proved that the reaction occurred and acrylate groups attached to the oil chain. 3.3.2. UV-vis spectra of acrylated black seed oil As can be seen in UV spectra that there were two peaks in range λmax = 217 - 268 nm. In that, the intensity of absorption at 255.6 – 268.4nm increase significantly to compare with black seed oil before acrylation. Thus, acrylate had attached to oil chain. 3.3.3 Nuclear magnetic resonance spectra of acrylated black seed oil The NMR spectra of acrylated black seed oil had similar shapes acrylated Vernonia oil. Comparison of resonance signals characteristic of the proton, carbon of acrylated black seed oil and acrylated Vernonia oil were presented in Table 3.7 Table 3.7. Comparison of data 1H-NMR, 13C-NMR between acrylated black seed oil and acrylated Vernonia oil Chemical shifts (δ, ppm) Acrylated black seed oil Acrylated Vernonia oil Types of proton Proton ethylene of acrylated oil Proton of metacrylated oil Proton neighbour acrylated và metacrylated ester Proton of hydroxyl group Proton methyl of metacrylate group Types of carbon Carbon of acrylate ester Carbon of metacrylate ester 6,4; 6,1; 5,8 5,56 - 6,22 6,5; 6,2; 5,8 6,05; 5,5 4,87 - 4,93 4,8 - 4,9 3,43 - 3,62 1,94 - 1,95 3,57 - 3,65 1,95 165,69 166,72 165,45 166,65 Carbon of double bond in the fisrt chain acrylate 131,09; 128,86 130,07; 128,1 Carbon of double bond in the fisrt chain metacrylate 136,2; 125,57 136; 125,6 The next stage will present the examation and analysis NMR spectra of acrylated black seed oil 3.3.3.1. Resonance signal 1H-NMR The 1H-NMR spectra, formula, the number of location and the results of analysis 1H-NMR spectra of acrylated black seed oil were presented in the Fig 3.10 and table 3.8. 12 Fig 3.10. 1H-NMR spectra of acrylated black seed oil. Table 3.8. Chemical shifts in the 1H-NMR characteristic protons of acrylated black seed oil H A B 1 2 3 4 5 6 7 8 9 10 Chemical shifts, δ( ppm) H Chemical shifts, δ( ppm) 4,12 (m, 2H) 4,31 (m, 2H) 5,33 (t, 1H) 2,20 (m) 1,61 - 1,67 (complex) 1,25 - 1,61 (complex) 1,25 - 1,61 (complex) 1,25 - 1,61 (complex) 1,25 - 1,61 (complex) 2,05 (m) 5,53 (t, 3H) 11 2,40 (m) 12 13 14 15 16 17 18 19 20a 20b 4,40 - 4,47 (t, 2H) 4,87 - 4,93 (t, 2H) 2,07 (m) 1,25 - 1,61 (complex) 1,25 - 1,61 (complex) 1,25 - 1,61 (complex) 0,86 - 0,89 (complex, 9H) 6,06 - 6,13 5,81 (m, 2H) 6,41 (m, 2H) 5,30 (t, 3H) 21 3,43 - 3,62 (s, 2H) 13 3.3.3.2. Resonance signal C-NMR The results of analysis 13C-NMR of acrylated black seed oil by acid acrylic were showed in the table 3.9. 13 Table 3.9. The chemicacl shifts in the 13C-NMR characteristic carbon atoms of acrylated black seed oil C Chemical shifts, δ (ppm) C Chemical shifts, δ (ppm) A 61,95 11 28,06 B 1 2 3 4 5 6 7 8 9 10 68,80 173,86 33,05 24,86 29,02 29,17 29,37 29,62 27,24 125,14 133,05 12 13 14 15 16 17 18 19 20 72,82 77,27 30,36 25,49 31,78 22,48 13,96 165,69 128,86 21 131,09 3.3.4 Mass spectrometry of acrylated black seed oil High resolution MS of acrylated black seed oil had a peak ion at m/z = 1057, respectively the mass of molecular acrylated black seed oil containing the acrylate group content 2.0 moles/mole oil and the thesis proposal the structural formula follow: There are several conclusions from the results of analysis structure acrylated black seed oil by acid acrylic and acid metacrylic:  Based on the the results of analysis IR, UV, NMR and MS, thesis had determined acrylated black seed oil containing hydroxyl, acrylate and ester.  Synthesized and determined acrylated black seed oil by acid acrylic containing acrylate group content from 0.47 to 2.0 moles acrylate/mole oil and acrylated black seed oil by acid metacrylic having 1.0 mole and 1.6 moles metacrylic/mole oil.  Structure of acrylated black seed oil indicated that this is a highly reactive compound and easily participates photo crosslinking. Thus, reaction of photo-crosslinking based on acrylated black seed oil has selected for further study in thesis. 14 3.4. Study on reaction of photo-crosslinking based on acrylated black seed oil system 3.4.1. Photo systems based on acrylated black seed oil with photo initator I.184 Table 2.1. Mass ratio of the constituents in the photo systems based on crosslinking acrylated black seed oil and photo initiator I.184 No 1 2 3 4 Constituents’ ratio (wp) Acrylated black seed oil DHCĐA2.0 DHCĐA1.6 DHCĐMA 1.6 DHCĐMA 1.0 I.184 3 3 3 3 3.4.1.1. Study IR of photo system before and after exposure UV. Table 3.10. The change of absorption characteristic functional group and group atoms of photo system based on acrylated black seed oil before and after 6 seconds exposure UV DHCĐA2.0/I.184 = Wave 100/3 number Characteristic -1 (cm ) before after 3505 Valence fluctuation of hydroxyl group + + 2856 Valence fluctuation symmetry and non-symmetry of C+ + 2927 H alkane 1738 Valence fluctuation of carbonyl group + + 1635 Valence fluctuation of double bond acrylate + 1410 Deformed oscillator in plane of CH2 acrylate + 988 + Deformed oscillator out of plane of CH2 acrylate 810 + Ghi chú:(+) absorption, (-) non-absorption, “” unchanged, “” decrease The change        As can be seen from the results of analysis IR, in the process of photo-crosslinking, intensity of absorption characteristic valence fluctuation of carbonyl at 1739 cm-1, hydroxyl at 3505cm-1 and C-H alkane at 2927cm-1 were almost unchanged. Absorption at 3467 cm characteristic valence fluctuation of hydroxyl, at 1729 cm of carbonyl increased. Absorptions at 1636cm-1, 1411cm-1, 989cm-1 và 811cm-1 characteristic valence fluctuation, deformed oscillator of double bond acrylate in the photo curing system dramatically fell. Therefore, absorption at 2927 characteristic of C-H alkane has been selected as the internal standard to examine the change of the content of the acrylate group at 1411 cm-1. 3.4.1.2. Influence of several factors on the photo-crosslinking reaction The process of photo-crosslinking depends on several factors such as: natural, the concentration of monomers, oligomers, film thickness, intensity and wavelength… The thesis concentrated on study on influence of content and natural acrylate group on the process of photo-crosslinking and the physic-mechanical coating.  The change of acrylate in the process of photo-crosslinking. Fig 3.11 presented the change of rate D1410/D2927 of photo-crosslinking system DHCĐA2.0 (●); DHCĐA1.6 (♦); DHCĐMA1.6 (▲); DHCĐMA1.0 (*) having diffirent content and natural acrylated in the exposure. As can be seen from fig 3.11, acrylate in all systems converted rapidly in the first 1.2 seconds exposure UV, before converting slow and almost being unchanged after 6 seconds exposure UV, reaching acrylate convertion 99; 96; 96; and 95%, respectively photo- 15 crosslinking systems DHCĐA2.0; DHCĐA1.6; DHCĐMA1.6; DHCĐMA1.0. As is seen, higher level of acrylated black seed oil made speed of reaction faster and acrylate experienced higher conversion than metacrylate. The conversion of acrylate group in the photo-crosslinking systems can be arranged follow order: DHCĐA2.0 > DHCĐA1.6 > DHCĐMA1.6 > DHCĐMA1.0 D 1410 / D2927 0.20 DHCĐA2.0/I.184 = 100/3 : ● DHCĐA1.6/I.184 = 100/3 : ♦ 0.15 0.10 DHCĐMA1.6/I.184 = 100/3 : ▲ DHCĐMA1.0/I.184 = 100/3 : * 0.05 0.00 0 1 2 3 4 5 6 7 Thời gian chiếu tia tử ngoại (giây) Time of exposure UV (second) Fig. 3.11. The change of rate D1410/D2927 of photo-crosslinking having diffirent content and natural acrylate in the process of exposure UV.  Gel fraction and Swelling degree Fig 3.12. presented the change of gel fraction and swelling degree of DHCĐA2.0(●); DHCĐA1.6 (♦); DHCĐMA1.6 (▲); DHCĐMA1.0 (*) having diffirent content and natural acrylate in the exposure UV. Gel fraction (%) Swelling degree (%) Phần gel (% ) 100 DHCĐA2,0/I.184 = 100/3 DHCĐMA1,6/I.184 = 100/3 Độ trương (% ) 1000 ● DHCĐA1,6/I.184 = 100/3 ▲ DHCĐMA1,0/I.184 = 100/3 ♦ * 80 800 60 600 40 400 20 200 0 0 0 1 2 3 4 5 6 7 Thời gian chiếu tia tử ngoại (giây ) Time of exposure UV (second) Fig 3.12. The change of gel fraction and swelling degree of systems having diffirent content and natural acrylate in the exposure UV. As can be seen from fig. 3.12, before exposure UV, all of samples completely dissolve in choloroform; that means the gel fraction of system equal 0%, but the gel fraction of DHCĐA2.0 increased to 29%, DHCĐA1.6 grew to 25%, DHCMĐA1.6 rose to 24%, DHCĐMA1.0 increased to 22% after 0.15s exposure UV. After 3.6s exposure UV, the gel fraction rose slowly and after 6s exposure the the gel fraction reached 74; 70.5; 64.5; 62.5%, respectively. The swelling degree of coating also showed the respective rule. After 6s exposure, the swelling degree of – – Thus, after 6s exposure UV, the photo-crosslinking systems based on acrylated black seed oil have crosslinked, creating a three-dimensional network and becoming mulch solid reviews. It is seen from the results of studies, the system having higher acrylate group content makes the 16 density of crosslinking coating increase and the cured acrylate system was closer than the cured metacrylate leading to increasing gel fraction and reducing swelling degree.  Relative hardness The results of examine the change of hardness of DHCĐA2.0(●); DHCĐA1.6 (♦); DHCĐMA1.6 (▲); DHCĐMA1.0 (*) having the diffirent content and natural acrylate in the exposure UV were presented in the Fig 3.13. Relative hardness Độ cứng tương đối 0.4 0.3 0.2 DHCĐA2,0 DHCĐMA1,6 ● ▲ DHCĐA1,6 ♦ DHCĐMA1,0 * 0.1 0 1 2 3 4 5 6 7 Thời gian chiếu tia tử ngoại (giây ) Time of exposure UV (second) Fig 3.13. The change of relative hardness of systems having diffirent content and natural acrylate in the exposure UV As can be seen from 3.13, after 6s exposure UV, the coatings were studied from liquid stage transferring to solid with high relative hardness 0.36;0.32;0.31;0.28, respectively. Thus, coating having higher acrylate content could create hardly 3D network to compare with coating having lower acrylate content. The metacrylate coatings did not cure as closely as their counterpart. The change of relative hardness accordance with the results of determining gel fraction, swelling degree and the change of acrylate of the studied samples in the exposure UV. There are several conclusions from the results of studies on influence of the content and natural acrylate on photo-crosslinking of acrylated black seed oil and I.184:  Due to reactive acrylate and metacrylate, the reaction of photo-crosslinking occurred rapidly with almost complete convertsion of acrylate group and determining the time reaction was after 3.6s exposure UV.  When exposure UV, the acrylate group converted rapidly, reaching 95 – 99% after 6s exposure UV and the speed of convertsion arranged follow rule: DHCĐA2.0 > DHCĐA1.6 > DHCĐMA1.6 > DHCĐMA1.0  The process of photo-crosslinking leaded to the change of physic-mechanical properties of coating. When increasing the content of acrylate or metacrylate, the density of crosslinking raised leading to growth of gel fraction, relative hardness, decrease of swelling degree. The density of crosslinking and the physic-mechanical properties of metacrylate coating saw lower than acrylate coating due to effect of space of methyl. 3.4.2. Photo-crosslinking systems based on acrylaed black seed oil, monomer, oligomers acrylate and I.184 Table 2.2. The mass of constituents ratio in the photo-crosslinking based on acrylated black seed oil, monomer, oligomer and I.184 No DHCĐA2.0 5 80 Monomer, oligomer acrylat HDDA DGEDA H4.12.2 20 0 0 I.184 3 17 6 7 8 9 10 11 12 13 60 40 80 60 40 80 60 40 40 60 0 0 0 0 0 0 0 0 20 40 60 0 0 0 0 0 0 0 0 20 40 60 3 3 3 3 3 3 3 3 3.4.2.1. Study on IR spectra and evolution of the change of functional group in the photocrosslinking As can be seen from the results of analysis IR, in the process of photo-crosslinking, intensity of absorption 1636, 1410, 982, 810cm-1 characteristic valence fluctuation and deformed oscillator of double bond acrylate and sum of acrylate in the photo-crosslinking dramatically reduced. Absorptions characteristic valence fluctuations of carbonyl, hydroxyl and C-H alkane at 2927 cm-1 were unchanged. Therefore, absorption at 2927 characteristic of C-H alkane has been selected as the internal standard to examine the change of the content of the acrylate group at 1411 cm-1. 3.4.2.2. Study on influence of natural and ratio black seed oil, monomer/oligomer acrylate on photo-crosslinking  Study on the change of total content acrylate The change of total acrylate in the system with diffirent ratio DHCĐA2.0/HDDA, DHCĐA2.0/DGEDM và DHCĐA2.0/H4.12.2 when exposure UV were presented in the fig. 3.14 – 3.16 D1410 / D 2927 D1410 / D 2927 0.25 0.40 DHCĐA2.0/HDDA: 80/20: ♦ 60/40: ● Tỉ lệ DHCĐA2.0/DGEDM: 40/60: ▲ 60/40 ● 80/20 ♦ 0.20 0.30 0.15 0.20 0.10 0.10 0.05 0.00 0 1 2 3 4 5 6 0.00 7 0 Thời gian chiếu tia tử ngoại (giây ) 1 2 4 5 6 7 Time of exposure UV (second) Fig 3.14. Influence of ratio DHCĐA2.0/HDDA on the convertsion total acrylate in the exporuse UV D 1410 / D Fig 3.15. Influence of ratio DHCĐA2.0/ DGEDM on the convertsion total acrylate in the exporuse UV 2927 0.6 DHCĐA2.0/H4.12.2: 80/20 ♦ 60/40 ● 40/60 ▲ 0.5 0.4 0.3 0.2 0.1 0.0 0 3 Thời gian chiếu tia tử ngoại (giây ) Time of exposure UV (second) 1 2 3 4 5 Thời gian chiếu tia tử ngoại (giây ) 6 Time of exposure UV (second) 7 18 Fig 3.15. Influence of ratio DHCĐA2.0/H4.12.2 on the convertsion total acrylate in the exporuse UV As can be seen from Fig 3.14 – 3.16, in the first 1.2s exposure UV the total content of acrylate converted rapidly, then it saw slower convertsion and after 6s exposure UV the performance of convertsion reached 99 (sample number 5) 98% (sample number 6), 94% (sample number 7), 92% (sample number 8), 81% (sample number 9), 87% (sample number 11), 85% (sample number 12) và 84% (sample number 13). The results of the change of acrylate group content of monomers/oligomers or mixture monomer and oligomer showed that chemical structure, rate of monomer/oligomer acrylate had effect on the convertsion of acrylate in the photo-crosslinking. These results were explained that: in the first stage, the compability of monomer/oligomer acrylate with acrylated black seed oil responsed capability as well as the convertsion of total acrylate group. Due to monomer HDDA, mixture of monomer and oligomer H4.12.2 had good compability with DHCĐA2.0 and beter mobility than DGEDM, photo-crosslinking containing monomer HDDA, mixture of monomer and oligomer H4.12.2 will have better capability and the faster convertsion of acrylate group in comparison with system containing DGEDM. In the next stage, when the network of polymer created, the capability as well as the conversion depends on the compability of the part of chain in the spacy network. Due to the part of chain established from monomer HDDA was more flexible and capable than that built from oligomer DGEDM or mixture of monomer, oligomer H4.12.2, photo-crosslinking system containing HDDA will having the higher conversion. The compabilities of monomers/oligomers acrylate were arranged the rule: HDDA > H4.12.2 > DGEDM.  Study on the change of gel fraction, swelling degree and physic-mechanical properties The results of the change gel fraction, swelling degree of sample 5 – 13 were showed in the Fig 3.17 – 3.19. Gel fraction (%) 100 Swelling degree (%) Độ trương (% ) Phần gel (% ) Gel fraction (%) 1000 80 800 60 600 40 400 20 200 DHCĐA2.0/HDDA: 80/20: ♦ 60/40: ● Swelling degree (%) Độ trương (% ) Phần gel (% ) 100 1000 80 800 60 600 40 400 DHCĐA2.0/DGEDM: 20 80/20: ♦ 60/40: ● 5 6 200 40/60: ▲ 0 0 0 1 2 3 4 5 Thời gian chiếu tia tử ngoại (giây ) 6 Time of exposure UV (second) 7 0 0 0 1 2 3 4 Thời gian chiếu tia tử ngoại (giây ) 7 Time of exposure UV (second) Fig 3.17. Influence of rate of DHCĐA2.0/HDDA Fig 3.18. Influence of rate of DHCĐA2.0/ on the change of gel fraction and swelling degree in DGEDM on the change of gel fraction and the process of exposure UV swelling degree in the process of exposure UV Fig 3.17 – 3.19 showed that after 0.6s exposure UV, the gel fraction of coating increased rapidly, and then it had a little change. After 6s exposure UV, the coating DHCĐA2.0/HDDA = 80/20, 60/40, 40/60 having gel fraction reached 75; 86; and 81%; the coating DHCĐA2.0/DGEDM = 80/20, 60/40, having gel fraction reached 79; and 71%; the coating DHCĐA2.0/ H4.12.2 74,7%. The change of swelling degree also showed the corresponding rule. After 6s exposure UV, the swelling degree of sample 5 reduced from 846% to 423%, sample 6 fell from 897% to