Availabeonineatwnwsciencedirect.con ScienceDirect NCE ELSEVIER Prog.Polm.Sci.31(2006983-1008 www.vicr.com/locate/ppoly Addition polymers from natural oils-A review Vinay Sharma,P.P.Kundu* Received 23 January 2006:received in revised form 14 September 2006:accepted 15 September 2006 Abstract Emerging technological knowledge is leading research into new ventures.One such is the conversion of natural oils to im pro sthe sour of polymeric raw mater polymers from natural ois.This review paper discusses the synthesis and characteriation of new polymers from diferent Keyrd Natural oil Dynamic mechanical analysis;Cross-inking Drying oi:Glass transition temperature Contents 1.Introduction 984 2.1.1. Unmodified soybean oil polymers Modified soybean oil polymers ers 252 Epoxidized linseed oil polymers Castor oil polymers.. Polymers from other oils.................................................... 3. 1006 References.... .1006 ing author.Tel:+91167283606:ax:+9116728365 E-mail address:ppk93@yahoo.com (P.P.Kundu). 0079-6700/S-see front ma
Prog. Polym. Sci. 31 (2006) 983–1008 Addition polymers from natural oils—A review Vinay Sharma, P.P. Kundu Department of Chemical Technology, Sant Longowal Institute of Engineering and Technology, Sangrur, Punjab 148106, India Received 23 January 2006; received in revised form 14 September 2006; accepted 15 September 2006 Abstract Emerging technological knowledge is leading research into new ventures. One such is the conversion of natural oils to polymers to augment the use of petroleum products as the source of polymeric raw materials. Natural oils, such as vegetable oils, now mainly used in the food industry, offer alternatives, and recent research has studied new routes of synthesis of polymers from natural oils. This review paper discusses the synthesis and characterization of new polymers from different natural oils such as soybean, corn, tung, linseed, castor, and fish oil. The effects of different levels of unsaturation in the natural oils and various types of catalysts and comonomers on the properties of copolymers are considered. r 2006 Elsevier Ltd. All rights reserved. Keywords: Natural oils; Dynamic mechanical analysis; Cross-linking; Polymerization; Drying oil; Glass transition temperature Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 984 2. Polymers from natural oils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 985 2.1. Soybean oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 985 2.1.1. Unmodified soybean oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 985 2.1.2. Modified soybean oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 992 2.2. Fish oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 994 2.3. Corn oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 995 2.4. Tung oil polymers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 996 2.5. Linseed oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 998 2.5.1. Natural linseed oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 998 2.5.2. Epoxidized linseed oil polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1002 2.6. Castor oil polymers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1003 2.7. Polymers from other oils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1004 3. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1005 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1006 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1006 ARTICLE IN PRESS www.elsevier.com/locate/ppolysci 0079-6700/$ - see front matter r 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.progpolymsci.2006.09.003 Corresponding author. Tel.: +91 16 7283606; fax: +91 16 7283657. E-mail address: ppk923@yahoo.com (P.P. Kundu).
984 V.Sharma.P.P.Kundu Prog.Polym.Sci.31 (2006)983-1008 1.Introduction poxies:It is apparent that on a mond epoxies with numerous le es of tion of resins and polymeric materials.to replaceor In addition to their application in the food industry augment the traditional petro-chemical based poly- triglyceride oils have been used for the production mers and resins.Natural oils such as linseed and of coatings.inks,plasticizers,lubricants and agro- tung oil have long found various uses in the paint chemicals [3-9].In general,drying oils (these can and varnishes industries.These oils have tradition polymerize in air to form a tough elastic lm)are ally been use organic er as resins o widely usec In these alt 0u出 the semi-drying o (the oil have also been used in polymerizations. s The mers obtat ped from natural Natural oils are tricglveeride esters of fatty acids oils are biopolymers in the sense that they are the general structure of which is shown in Fig.1. generated from renewable natural sources;they are Triglycerides comprise three fatty acids joined by a often biodegradable as well as non-toxic. glycerol center [1].Most of the common oil contains Some biopolymers obtained from natural oils are fatty acids tha 2 carbons in flexible and rubbery.Generally,they are prepared al polye number o with other e.g rated bac fatty acid chai -oleic acid chain linoleic acid chain linolenic acid chain nter.Reprinted with permission from Polymer2001 Table I Main fatty acid contents in different ois Fatty acid C:#DB]Canola oil Com oi Cottonseed oil Linseed oil Olive oil Soybean oil Tung oil Fish oi 180 86 853 10.0 18.2 183 8.8 0.7 56.6 0.6 7.8 0.99 3.9 4.5 3.9 6.6 28 4.6 3.6 "Fish oils tend to in a high double bond co example.the co
1. Introduction In recent years natural oils have attracted renewed attention as raw materials for the preparation of resins and polymeric materials, to replace or augment the traditional petro-chemical based polymers and resins. Natural oils such as linseed and tung oil have long found various uses in the paint and varnishes industries. These oils have traditionally been used in organic coatings either as resins or as a raw material for the preparation of resins. Soybean oil, safflower oil, sunflower oil and canola oil have also been used in polymerizations. Natural oils are tri-glyceride esters of fatty acids, the general structure of which is shown in Fig. 1. Triglycerides comprise three fatty acids joined by a glycerol center [1]. Most of the common oil contains fatty acids that vary from 14 to 22 carbons in length, with 1–3 double bonds. The fatty acid distribution of several common oils is shown in Table 1 [1]. In addition, there are some oils comprise fatty acids with other types of functionalities (e.g., epoxies, hydroxyls, cyclic groups and furanoid groups) [2]. It is apparent that on a molecular level, these oils are composed of many different types of triglyceride, with numerous levels of unsaturation. In addition to their application in the food industry, triglyceride oils have been used for the production of coatings, inks, plasticizers, lubricants and agrochemicals [3–9]. In general, drying oils (these can polymerize in air to form a tough elastic film) are the most widely used oils in these industries, although the semi-drying oils (these partially harden when exposed to air) also find use in some applications. The polymers obtained from natural oils are biopolymers in the sense that they are generated from renewable natural sources; they are often biodegradable as well as non-toxic. Some biopolymers obtained from natural oils are flexible and rubbery. Generally, they are prepared as cross-linked copolymers. Bacterial polyesters are obtained from a large number of bacteria when subjected to metabolic stress. The cross-linking process for unsaturated bacterial polyester is shown ARTICLE IN PRESS O O O O O O glycerol center oleic acid chain linoleic acid chain linolenic acid chain fatty acid chain three ester bonds Fig. 1. The triglyceride chain containing three fatty acid chains joined by a glycerol center. Reprinted with permission from Polymer 2001; 42: 1569 r Elsevier Science Ltd., [10]. Table 1 Main fatty acid contents in different oils Fatty acid [#C: #DB] Canola oil Corn oil Cottonseed oil Linseed oil Olive oil Soybean oil Tung oil Fish oily Palmitic 16:0 4.1 10.9 21.6 5.5 13.7 11.0 — — Stearic 18:0 1.8 2.0 2.6 3.5 2.5 4.0 4 — Oleic 18:1 60.9 25.4 18.6 19.1 71.1 23.4 8 18.20 Linoleic 18:2 21.0 59.6 54.4 15.3 10.0 53.3 4 1.10 Linolenic 18:3 8.8 1.2 0.7 56.6 0.6 7.8 — 0.99 a-elaeostearic acid — — — — — — — 84 — Average #DB/triglyceride. — 3.9 4.5 3.9 6.6 2.8 4.6 7.5 3.6 Reproduced with the permission from J Appl Polym Sci 2001; 82: 703 r John Wiley and Sons, Inc. [1]. #C stands for number of carbon atoms in chain and #DB stands for the number of double bonds in that chain. y Fish oils tend to contain a high double bond content; for example, the composition of a Norway fish oil examined in one study contained a fatty acid (ethyl ester) composition with 8.90% having no double bonds, 6.03% having four double bonds, 37.25% having EPA or DPA and 24.72% (DHA) having six double bonds [29]. 984 V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008
V.Sharma.P.P.Kundu Prog.Polym.ScL.31(2006)983-1008 985 in Fig.2,describing the cross-linking of the with cyclohexane dicarboxylic acid.Scheme 2(b) unsaturated bacterial polyesters prepa red from shows the oligomerization with maleic acid,which soybean oily fatty acids.It is observed that cross- introduces more double bonds in the oligomers. linking occurs in at least two polyester chain double bonds.Scheme I describes the representative 2.Polymers from natural oils 2.1.Soybean oil polymers ctherate.Schem nodified acrylated epoxidized s bean oil (AESO) ed from s with reagents selected to stiffen the polymer chain. extensivelyinvestigated by Larock Scheme 2(a)shows the oligomerization of an AESO soybean oils are biodegradable vegetable oil,readily -CH- CH -CH-CH -3-0—H0 CH --0 with the permission from Polym 69 wwwCH-CHww modified initiato
in Fig. 2, describing the cross-linking of the unsaturated bacterial polyesters prepared from soybean oily fatty acids. It is observed that crosslinking occurs in at least two polyester chain double bonds. Scheme 1 describes the representative process of cationic copolymerization of the triglyceride oil with styrene and divinylbenzene in the presence of a modified boron trifluoride diethyl etherate. Scheme 2 shows the oligomerization of a modified acrylated epoxidized soybean oil (AESO) with reagents selected to stiffen the polymer chain. Scheme 2(a) shows the oligomerization of an AESO with cyclohexane dicarboxylic acid. Scheme 2(b) shows the oligomerization with maleic acid, which introduces more double bonds in the oligomers. 2. Polymers from natural oils 2.1. Soybean oil polymers 2.1.1. Unmodified soybean oil polymers Polymers derived from soybean oils have been extensively investigated by Larock et al. [10–15]; soybean oils are biodegradable vegetable oil, readily ARTICLE IN PRESS CH CH2 C O O CH CH2 C O O HC CH2 C O O CH CH2 C O O CH CH2 C O O CH CH2 C O O Fig. 2. The cross-linking process of bacterial polyester obtained from soybean oily fatty acids. Reprinted with the permission from Polym Bull 2001; 46: 393 r Springer-Verlag, Inc. [24]. CO2 CO2 CO2 CH CH CH CH CH CH + + m n H2 C O O C O CH CH C O C O CH2 CH HC CH CH CH CH2 CH CH2 CH m Scheme 1. The proposed process of cross-linking of natural oil with styrene and divinylbenzene in presence of modified initiator. Reprinted with the permission from J Appl Polym Sci 2003; 90: 1832 r Wiley Periodicals, Inc. [30]. V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008 985
986 V.Sharma.P.P.Kundu/Prog.Polym.Sci.31(2006)983-1008 8 入入⑧入入 2.b t9e80ne。一 available in bulk;specification of soybean oils used various polymers. Cationic copolymerization of Larock group are reportec in regular soybean oil,low n o a trigly e struc. soybe The H NMR shown in Fig These makes them ideal monomers for the preparation of analysis (DMA).thermogravimetric analysis
available in bulk; specification of soybean oils used by the Larock group are reported in Table 2. Natural soybean oil possesses a triglyceride structure with highly unsaturated fatty acid side chains. The 1 H NMR spectra of some example oils are shown in Fig. 3. The unsaturation in these oils makes them ideal monomers for the preparation of various polymers. Cationic copolymerization of regular soybean oil, low saturated soybean oil or conjugated low saturated soybean oil with styrene and divinylbenzene leads to various copolymers. These copolymers have been characterized by various techniques, including dynamic mechanical analysis (DMA), thermogravimetric analysis ARTICLE IN PRESS Scheme 2. The modification of acrylated epoxidized soybean oil (AESO) shown using cyclohexane dicarboxylic anhydride or maleic anhydride. These AESOs were cured with styrene or other comonomers. Reprinted with the permission from J Appl Polym Sci 2001; 82: 707 r John Wiley and Sons, Inc. [1]. 986 V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008
V.Sharma.P.P.Kundu Prog.Polym.Scl.31(2006)983-100 981 之ima时n al dteaihn ef op Soybean oil C==C Fatty acids" Type No.? C16.0 C180 C18:1 C18:2 C183 an oil 3品 Conjugated saturated soybean oil Conjugated 5.1 5.0 3.0 20.0 64.0 9.0 For example.C18:2 represent the fatty acid (ester)that possesses 18 carbons and 2 C==C bonds cu-C-and -CH-CC- 人人U 7.0 50 30 20 10 0. crpy t0m的DsO therma Th me anc of the sovbean oil with onon er initiated by bo on tri- reported in Table 3.The vield of the cross-linked fluoride diethyl etherate results in polymers rangir product depends on the concentration of the cross. from soft rubbers to hard thermosets,depending on linking agents,such as divinylbenzene.dicyclopen- the oil and the stoichiometry employed [10].It was tadiene.etc.As usual.cross-linking increases the found that the initiator was immiscible with these glass transition temperature of the polymer.Poly- mers from different soybean oils show was mo properties,and the on of soybean oil polymers c aeuedhravoh on trifluoride diethyl eth on o resulted in polymers with good mechanical proper. ties and thermal stability. extraction,with the results shown in Tables 4 and 5. It has been observed that the copolymerization of From these results.it was clear that the composition soybean oils with other comonomers results in a of the copolymer dictated the properties.For network.with a gelation time dependent on the example,the oily component of the copolymer
(TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and thermal mechanical analysis (TMA). Cationic polymerization of the soybean oil with divinylbenzene comonomer initiated by boron tri- fluoride diethyl etherate results in polymers ranging from soft rubbers to hard thermosets, depending on the oil and the stoichiometry employed [10]. It was found that the initiator was immiscible with these oils, but that miscibility was vastly improved when the initiator was modified with a norway fish oil ethyl ester. The copolymerization of soybean oil with styrene and norbornadiene or dicyclopentadiene initiated by boron trifluoride diethyl etherate resulted in polymers with good mechanical properties and thermal stability. It has been observed that the copolymerization of soybean oils with other comonomers results in a network, with a gelation time dependent on the stoichiometry and type of the triglyceride oil used [11]. The gelation time and yield for various copolymers prepared from varying concentrations of the oils, comonomers and modified initiators is reported in Table 3. The yield of the cross-linked product depends on the concentration of the crosslinking agents, such as divinylbenzene, dicyclopentadiene, etc. As usual, cross-linking increases the glass transition temperature of the polymer. Polymers from different soybean oils show different properties, and the cross-linking density of the bulk polymers considerably affected their thermophysical properties [12]. Several copolymers obtained from copolymerization of a soybean oil with divinylbenzene were characterized by DMA, TGA and soxhlet extraction, with the results shown in Tables 4 and 5. From these results, it was clear that the composition of the copolymer dictated the properties. For example, the oily component of the copolymer ARTICLE IN PRESS Fig. 3. The 1 H NMR spectra of different soybean oils. (a) regular soybean oil, (b) low saturated soybean oil and (c) conjugated low saturated soybean oil. Reprinted with permission from J Appl Polym Sci 2001; 80: 660 r John Wiley and Sons, Inc. [11]. Table 2 The composition of the soybean oils used for the preparation of copolymers Soybean oil CQQC Fatty acidsb Type No.a C16:0 C18:0 C18:1 C18:2 C18:3 Regular soybean oil Non-conjugated 4.5 10.5 3.2 22.3 54.4 8.3 Low saturated soybean oil Non-conjugated 5.1 5.0 3.0 20.0 64.0 9.0 Conjugated saturated soybean oil Conjugated 5.1 5.0 3.0 20.0 64.0 9.0 Reproduced with the permission from J Polym Sci: Part B: Polym Phys 2000; 38: 2722 r John Wiley and Sons, Inc. [12]. a The average number of carbon-carbon double bonds was calculated by 1 H NMR spectral analysis. b For example, C18:2 represent the fatty acid (ester) that possesses 18 carbons and 2 CQQC bonds. V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008 987
988 V.Sharma.P.P.Kundu Prog.Polym.Sci.31 (2006)983-1008 Table 3 Original composition (wt%) Gelation time (s) Yield(%)of cross linked polymer after extraction Triglyceride oil Comonomers Initiators 45%LSS 32%ST+15%DVB 5%SG-I+3%BFE 3.0×10 45%L5s 29ST+159%DvE 30×10 5%NF0t3% 3.0× 45%CLS 32%ST+15%DVB 5%NFO+3%BFE 6.6×10 45%CLS 32%ST+15%DC 39%6NF0+39%BFE 2.1×10 Reproduced with the permission from J Appl Polym Sci 2001:80:662 John Wiley and Sons,Inc.[11] TtAMA.TGA.andSotitetiacioareifactcanplkspparodbyeopo ocrization of sovbcan oil and divinvlbenzcne in the presence of modified initiator Polymer sample TC) Structure (wt% TGA (C) Cross-linked Free oil Ine.oil To Tso 760 16 SOY6o-DVB25-NFOI-BFES) IS-DVB NFOIO-BFES) 3 0 LSSSS-DVB30-(NFO10-BFE5) 835 70507007 080 CLS50-DVB3S-NFOI-BEES 13578603244 970245 CLS40-DVBNFO-BEES 78 12 Reproduced with the pe rmission from Polymer 2001:42:1573 C Elsevier Science Ltd..I10L E c二Young's m s at room temperature. .Here SOY re noil,CLS- -No induces reduction in the glass transition tempera- at temperatures dependent on the oil,e.g..68C for ture,stiflness and modulus. regula soybean oil,61C for low saturated soybean The variation of the storage modulus(F)and loss oil and 76C for conjugate d low saturated soybean temperature is s hown in Figs. oil.This single loss pea ind cates that the polymer ers prepare omogeneous phase the gated low saturated soybean oil.In Fig 5.the and stor moduli polymers from these oils exhibited a single loss peak prepared from soybean oi
induces reduction in the glass transition temperature, stiffness and modulus. The variation of the storage modulus (E0 ) and loss factor (tan d) with temperature is shown in Figs. 4 and 5, respectively, for several copolymers prepared from regular soybean oil. In Fig. 4, E0 is minimum for regular soybean oil and maximum for conjugated low saturated soybean oil. In Fig. 5, the polymers from these oils exhibited a single loss peak at temperatures dependent on the oil, e.g., 68 1C for regular soybean oil, 61 1C for low saturated soybean oil and 76 1C for conjugated low saturated soybean oil. This single loss peak indicates that the polymers had a homogeneous phase. From these results, it is clear that in all soybean oils used, the conjugated low saturated soybean oil gave the highest crosslinking density, glass transition and storage moduli. Copolymers were also prepared from soybean oil ARTICLE IN PRESS Table 4 The DMA, TGA, and Soxhlet extraction results for the samples prepared by copolymerization of soybean oil and divinylbenzene in the presence of modified initiator Polymer samplea Eroom(Pa) 108 ne(mol/m3 ) 103 Tg(1C) Structure (wt%) TGA (1C) a1 a2 Cross-linked Free oil Inc. oilb T10 T50 SOY60-DVB35-BFE5 4.0 7.60 27 — 69 31 29 415 490 SOY50-DVB35-(NFO10-BFE5) 5.0 11.6 70 10 77 23 37 425 491 SOY55-DVB30-(NFO10-BFE5) 2.5 6.51 15 5 75 25 40 380 475 SOY60-DVB25-(NFO10-BFE5) 1.7 4.18 20 0 73 27 43 360 470 LSS60-DVB35-BFE5 6.0 10.4 37 - 82 18 42 423 485 LSS50-DVB35-(NFO10-BFE5) 7.0 13.0 70 0 84 16 44 425 486 LSS55-DVB30-(NFO10-BFE5) 3.8 8.35 30 8 80 20 45 405 486 LSS60-DVB25-(NFO10-BFE5) 1.9 4.18 17 0 77 23 47 395 485 CLS50-DVB35-(NFO10-BFE5) 12 18.9 90 - 88 22 48 440 485 CLS55-DVB30-(NFO10-BFE5) 10 11.4 80 - 86 14 51 436 486 CLS60-DVB25-(NFO10-BFE5) 7.8 7.21 68 - 86 14 56 433 483 Reproduced with the permission from Polymer 2001; 42: 1573 r Elsevier Science Ltd., [10]. Eroom ¼ Young’s modulus at room temperature. ne ¼ Cross-linking density. a Here SOY represents regular soybean oil, LSS—Low saturated soybean oil, CLS—conjugated low saturated soybean Oil, DVB— divinylbenzene, NFO—Norway Pronova fish oil ethyl ester and BFE —boron trifluoride diethyl etherate. The numerals, such as SOY60 represents 60 wt% of soybean oil. b Wt% of oil incorporated into the cross-linked network. Table 3 The results from copolymerization of different soybean oils using different modified initiator system with styrene and divinylbenzene, norbornadiene or dicyclopentadiene Original composition (wt%) Gelation time (s) Yield (%) of cross linked polymer after extraction Triglyceride oil Comonomers Initiators 45% LSS 32%ST+15%DVB 5%SG-I+3%BFE 3.0 102 83 45% LSS 32%ST+15%DVB 5%SG-II+3%BFE 3.0 102 82 45% LSS 32%ST+15%DVB 5%SG-III+3%BFE 3.0 102 83 45% LSS 32%ST+15%DVB 5%NFO+3%BFE 3.0 102 84 45% SOY 32%ST+15%DVB 5%NFO+3%BFE 2.4 102 80 45% LSS 32%ST+15%DVB 5%NFO+3%BFE 3.0 102 84 45% CLS 32%ST+15%DVB 5%NFO+3%BFE 6.6 102 92 45% CLS 32%ST+15%DVB 5%NFO+3%BFE 6.6 102 92 45% CLS 32%ST+15%NBD 5%NFO+3%BFE 3.5 103 89 45% CLS 32%ST+15%DCP 5%NFO+3%BFE 2.1 105 80 Reproduced with the permission from J Appl Polym Sci 2001; 80: 662 r John Wiley and Sons, Inc. [11]. 988 V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008
V.Sharma.P.P.Kundu Prog.Polym.Scl.31(2006)983-100 989 Polymer sample 7(g(molm×102 E(mpa)(mpa)(%)Toughness (mpa) 53 CLS45st32-DVB15-(NFO5-BFE3) 225 40.5 Reproduced with the permision from Polym Sci:Part B:Polym 62John Wiley and Sons,Ine.[ 1.E+10- SOY45-ST32-DVBIS-(NFO5-BFE 1.E+09 CLS45-ST32-DVBIS-(NFOS-BFES 1E+08 1 L.E40 05 1.E+06 土然電 1.E+05 1 125 are (C) 35155254565510s125 Temperature Fig.4.The temperature dependence of the storage modulus (E) regular soybean oil (SOY) enzene (DVB).using vay fis () Inc.[12. and divinylbenzene,using boron trifluoride diethyl low saturated soybean oil polymers show a yield etherate,resulting in heterogeneous polymeric point. materials [10]. The tensile fracture surface of polymer samples The tensile properties of several soybean oil (with 35 weight conjugated low saturated stomers har soybean oil)was observe d under a se polymers ope and n very similar SEM r the tensile strength fracture surface nd the mist fracture hreak decreases with an increase in the degree of surface are shown in Figs.7(a)and 7(b),respec cross-linking.At lower strain(<10%),the increase tively.for one sample. in stress is rapid,while at higher strain(0%),the The results for damping properties of several regular and low saturated soybean oil polymers soybean oils over a broad range of temperature and exhibit a slow increase in the stress.The conjugated frequency are reported in Table 6 [14].The high
and divinylbenzene, using boron trifluoride diethyl etherate, resulting in heterogeneous polymeric materials [10]. The tensile properties of several soybean oil polymers ranging from elastomers to hard, ductile and relatively brittle polymers are shown in Fig. 6 [13]. Generally, it is observed that the ultimate tensile strength increases and the elongation at break decreases with an increase in the degree of cross-linking. At lower strain (o10%), the increase in stress is rapid, while at higher strain (410%), the regular and low saturated soybean oil polymers exhibit a slow increase in the stress. The conjugated low saturated soybean oil polymers show a yield point. The tensile fracture surface of polymer samples (with 35 weight % conjugated low saturated soybean oil) was observed under a scanning electron microscope and shown to be very similar to those of epoxies [Fig. 7]. The SEM micrograph of the fracture surface and the mist region of the fractured surface are shown in Figs. 7(a) and 7(b), respectively, for one sample. The results for damping properties of several soybean oils over a broad range of temperature and frequency are reported in Table 6 [14]. The high ARTICLE IN PRESS Table 5 The tensile test results for various soybean oils Polymer sample Tg (1C) ne (mol/m3 ) 102 E (mpa) sb (mpa) eb (%) Toughness (mpa) SOY45st32-DVB15-(NFO5-BFE3) 68 1.8 71 4.1 57.1 1.67 LSS45st32-DVB15-(NFO5-BFE3) 61 5.3 90 6.0 64.1 2.86 CLS45st32-DVB15-(NFO5-BFE3) 76 22 225 11.5 40.5 4.00 Reproduced with the permission from J Polym Sci: Part B: Polym Phys 2000; 39: 62 r John Wiley and Sons, Inc. [13]. Tg ¼ Glass transition temperature. ne ¼ Cross-linking density. E ¼ Young’s modulus. sb ¼ Ultimate tensile strength. eb ¼ Elongation at break. SOY45-ST32-DVB15-(NFO5-BFE3) LSS45-ST32-DVB15-(NFO5-BFE3) CLS45-ST32-DVB15-(NFO5-BFE3) Temperature (°C) 1. E+10 1. E+09 1. E+08 1. E+07 1. E+06 1. E+05 Storage Modulus (Pa) -35 -15 5 25 45 85 105 12 65 5 Fig. 4. The temperature dependence of the storage modulus (E0 ) on the copolymers prepared from regular soybean oil (SOY), Lowsat soy oil (LSS) and conjugated Lowsat soy oil (CLS) with styrene (ST) and divinylbenzene (DVB), using Norway fish oil modified initiator. Reprinted with permission from J Polym Sci: Part B: Polym Phys 2000; 38: 2726 r John Wiley and Sons, Inc. [12]. -35 -15 5 25 45 85 105 125 Temperature Tan δ SOY45-ST32-DVB15-(NFO5-BFE3) 0 0.5 1 1.5 CLS45-ST32-DVB15-(NFO5-BFE3) LLS45-ST32-DVB15-(NFO5-BFE3) 65 Fig. 5. The temperature dependence of the loss modulus (tan d) for the copolymers prepared from regular soybean oil (SOY), Lowsat soy oil (LSS) and conjugated Lowsat soy oil (CLS) with styrene (ST) and divinylbenzene (DVB), using Norway fish oil modified initiator. Reprinted with permission from J Polym Sci: Part B: Polym Phys 2000; 38: 2727 r John Wiley and Sons, Inc. [12]. V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008 989
990 V.Sharma.P.P.Kundu Prog.Polym.Sci.31 (2006)983-1008 SOY45-ST32-DVBIS-(NFOS-BFES ·X @ 0 40 60 Strain(%) Poly damping intensities are ascribed to the contribution d sur from the large number of ester groups directly e-divinylbenzene he samp e and the mist region of the Polym Phys 2000:39:Wiley and Sons.Inc.3 in e e w al cro The three s ovbean oil p olymers showed the same glass transition temperature.but differ in the value of the loss tangent maxima.The broad damping have applications in civil construction.mechanics e T o and manufacturing.electronics and communica induced on cross-linking. However. tions,printing and packaging.medical equipment. also reduced the damping intensities by restricting recreation and sports,and household items the polymer segm the homogene mec tha anica h mers s at relatively high ten tures [16-191.Shape olymers to form interpenetrating networks (IPN)with a CItiCtophasaeicriblephaeanda fixed phase.The reversible phase refers to the polymer matrix,which has a glass transition facilitated by temperature (T)or a melting temperature (Tm) rom the forma well above the applicatio rather than by the segmenta phase or physi polymer th le at a temp mryrefer to the the sha memory olymer achieves a rubbery elastic state in
damping intensities are ascribed to the contribution from the large number of ester groups directly attached to the soybean oil–styrene–divinylbenzene copolymer chains. The variation in the glass transition temperature with cross-linking density is shown in Fig. 8 for several soybean oil polymers. The three soybean oil polymers showed the same glass transition temperature, but differ in the value of the loss tangent maxima. The broad damping regions were attributed to segmental inhomogeneity induced on cross-linking. However, cross-linking also reduced the damping intensities by restricting the polymer segmental motions of the homogeneous polymeric materials. Thus, it is expected that efficient damping materials (for sound and vibrational applications) would result on the chemical or physical combination of two or more structurally dissimilar soybean oil-based polymers to form interpenetrating networks (IPN) with a phase separated morphology. In such a case, broad damping regions would be facilitated by phase microheterogeneity resulting from the formation of IPNs, rather than by the segmental inhomogeneity [14]. Some soybean oil polymers prepared by cationic copolymerization show a good shape-memory effect [15]. Shape-memory refers to the ability of some materials to remember a specific shape on demand, even after very severe deformation. Such materials have applications in civil construction, mechanics and manufacturing, electronics and communications, printing and packaging, medical equipment, recreation and sports, and household items. A shape-memory polymer exhibits mechanical behavior that includes fixing the deformation of the plastics at room temperature and recovering the deformation as elastomers at relatively high temperatures [16–19]. Shape-memory polymers basically consist of two phases: a reversible phase and a fixed phase. The reversible phase refers to the polymer matrix, which has a glass transition temperature (Tg) or a melting temperature (Tm) well above the application temperature. The fixed phase is composed of either chemical or physical cross-links that are relatively stable at a temperature higher than the Tg or Tm of the reversible phase. At a temperature above Tg or Tm, the shapememory polymer achieves a rubbery elastic state in ARTICLE IN PRESS 0 20 40 60 80 Strain (%) 0 4 8 12 Stress (MPa) SOY45-ST32-DVB15-(NFO5-BFE3) CLS45-ST32-DVB15-(NFO5-BFE3) LLS45-ST32-DVB15-(NFO5-BFE3) Fig. 6. The tensile stress-strain curves from three soybean oil polymers i.e. regular (SOY), low saturated (LSS) and conjugated low saturated (CLS) soybean oil polymers for same percentage of oil and comonomers styrene (ST) and divinylbenzene (DVB). Reprinted with permission from J Polym Sci: Part B: Polym Phys 2000; 39: 63 r John Wiley and Sons, Inc. [13]. Fig. 7. The SEM micrograph of sample CLS35ST39-DVB18- (NFO5-BFE3) highlighting the mechanically fractured surface of the sample and the mist region of the mechanically fractured surface. Reprinted with permission from J Polym Sci: Part B: Polym Phys 2000; 39: 75 r John Wiley and Sons, Inc. [13]. 990 V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008
V.Sharma.P.P.Kundu Prog.Polym.Scl.31(2006)983-100 991 for the dampin perti of th oord Polymer sample TC)ve(mol/m)(tan (tan AT at tan 6>0.3 (C)TA (K)Half-width (C) SYADVBISNTO-E 46 SO39-DV S-NNFO .0x10 6 _SS45st32-DVBl5-(NFO5-BFE3) 0.8 03 19-9778 CLS35st39-DVBI8-(NFOS-BFE3 4×10 0 007 58668 CLSS-DVB1ANF8-BFE周 5127454 Reproduced with permission from Polymers for Advanced Technologies 2002:13:439.441 e John Wiley and Sons.Ltd..I41. Glass n te mperature )=Loss ngent maxima 120 the strong relaxations of the oriented polymer chains between the cross-links. Table 7 shows the shape-memory properties of several soybean oil polymers.It is observed that the type of soybean oil greatly affects the shape 80 hese polymers (e.g.,se rs fr ehertdieenabiyat than T.(D value).All of ther ric materials showve()ed deformationpo reheating to T:plus 50C. 10 The time for gelation and vitrification of various soybean oil polymer systems has been investigated CLS45-(ST+DVB)47-(NFO5-BFE3) fully cured t rst mac 10 100 1000 10000 100000 v.(mol/m dynamic resultin 一dma"anical benavoro curing conditions.However,varying the curing time at low and high temperatures did affect the structural c characteristics of the polymer backbone. which it can be easily deformed by an external force affecting the shape-memory and tensile mechanical n temperatur properties. hermal time-temperatur frozen micr mation ( am,developed to hardened reversible phase effectively re the s of the recovery resulting from the tendeney of the ordered chains to return to a more random state,but the at which the system gels and vitrifies simulta deformed shape readily returns to its original shape neously)and T(maximum T of fully cured upon heating above T or Tm.The driving force for system),where gelation precedes vitrification,are of the shape recovery is primarily entropy,especially practical importance.It was observed that gelation
which it can be easily deformed by an external force. When the polymer is cooled to room temperature, the deformation is fixed due to the frozen micro Brownian motion of the reversible phase. The hardened reversible phase effectively resists elastic recovery resulting from the tendency of the ordered chains to return to a more random state, but the deformed shape readily returns to its original shape upon heating above Tg or Tm. The driving force for the shape recovery is primarily entropy, especially the strong relaxations of the oriented polymer chains between the cross-links. Table 7 shows the shape-memory properties of several soybean oil polymers. It is observed that the type of soybean oil greatly affects the shapememory properties of these polymers (e.g., see No. 1–3). The polymers from reactive soybean oil show higher degree of fixed deformation (FD value) and a lower deformability at a temperature higher than Tg (D value). All of the polymeric materials show 100% recovery (R) of fixed deformation upon reheating to Tg plus 50 1C. The time for gelation and vitrification of various soybean oil polymer systems has been investigated over a range of isothermal curing temperatures [20]. All the fully cured thermosets were first made at room temperature and then subjected to post-curing at elevated temperatures. The thermal stability and dynamic mechanical behavior of the resulting thermosets were not particularly sensitive to the curing conditions. However, varying the curing time at low and high temperatures did affect the structural characteristics of the polymer backbone, affecting the shape-memory and tensile mechanical properties. The isothermal time–temperature–transformation (TTT) cure diagram, developed to study the epoxy systems [21–23], is a very useful tool for investigating the cure process of the soybean oil systems. The cure temperatures between Tg,gel, (Tg at which the system gels and vitrifies simultaneously) and TgN (maximum Tg of fully cured system), where gelation precedes vitrification, are of practical importance. It was observed that gelation ARTICLE IN PRESS υe (mol/m3) 10 100 1000 10000 100000 0 20 40 60 80 100 T g (°C) 120 SOY45-(ST+DVB) 47-(NFO5-BFE3) LSS45-(ST+DVB) 47-(NFO5-BFE3) CLS45-(ST+DVB) 47-(NFO5-BFE3) Fig. 8. The dependence of the glass transition temperature (Tg) on cross-linking density (ne) for different soybean oil polymers. Reprinted with permission from Polym Adv Technol 2002; 13: 444 r John Wiley and Sons, Ltd. [14]. Table 6 Results for the damping properties of the copolymers prepared from different soybean oils Polymer sample Tg(1C) ne(mol/m3 ) (tan d)max (tan d)rt DT at tan d40.3 (1C) TA (K) Half-width (1C) SOY35st39-DVB18-(NFO5-BFE3) 79 4.7 102 0.88 0.12 52–115 (63) 37.5 47 SOY45st32-DVB15-(NFO5-BFE3) 68 1.8 102 0.85 0.32 23–113 (90) 48.4 61 SOY55st25-DVB12-(NFO5-BFE3) 30 1.0 102 0.84 0.83 2–65 (67) 36.3 51 LSS35st39-DVB18-(NFO5-BFE3) 80 7.3 102 0.86 0.11 23–113 (90) 48.4 51 LSS45st32-DVB15-(NFO5-BFE3) 61 5.3 102 0.89 0.37 19–97 (78) 46.2 52 LSS55st25-DVB12-(NFO5-BFE3) 32 3.9 102 1.00 0.96 6–83 (89) 50.1 57 CLS35st39-DVB18-(NFO5-BFE3) 82 3.4 103 0.94 0.07 58–116 (58) 41.8 42 CLS45st32-DVB15-(NFO5-BFE3) 76 2.2 103 0.79 0.18 48–120 (72) 43.1 53 CLS55st25-DVB12-(NFO5-BFE3) 38 6.5 102 1.08 0.80 10–77 (67) 52.9 44 Reproduced with permission from Polymers for Advanced Technologies 2002; 13: 439,441 r John Wiley and Sons, Ltd., [14]. Tg ¼ Glass transition temperature. ne ¼ Cross-linking density. (tan d)max ¼ Loss tangent maxima. (tan d)rt ¼ Loss tangent at room temperature. TA ¼ tan d area. V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008 991
992 V.Sharma.P.P.Kundu Prog.Polym.Sci.31 (2006)983-1008 Polymer sample T(C)v.(mol/m')Shape memory results (% D FD R SOY4SST32-DVBI5-(NFOS-BFE3) 18×10 CLS45ST32-DVBIS-(NFOS-BFE3 22x10 VB9-NBDD(DVBS- 8650848 T0000 BD9 CP9)-(NFO5-BFE3) Joual of Applied Polymer:84:1539John Wiley and Sons,Ltd..[15] ross-linking density ner than t 52 occurs at app 15% of the group. LaScala and Wool et al.analyzed optimization only about 50%of the soybear oil reactants were of the effect of chemical functionaliza on on the converted into cross-linked polymers when the mechanical properties and thermal stability of some system vitrified.Thus,in order to obtain fully cured resins.The viscoelastic properties of resin samples networks,the materials were subsequently post- made of AESO and cured at room temperature with cured at elevated temperatures. varying amounts of styrene were studied.The H 2.1.2.Modified soybean oi polymers spectra of AESO are shown in Fig.9.Some own I tha at such as the double be nd.t trigly rs The 333w0 the allylic carbons,and the carbons to the este a 2:1 AESO to styrene rat io.was considered optimal
occurs at approximately 15% conversion of the reactants, and the yield of cross-linked polymers continued to increase following gelation. However, only about 50% of the soybean oil reactants were converted into cross-linked polymers when the system vitrified. Thus, in order to obtain fully cured networks, the materials were subsequently postcured at elevated temperatures. 2.1.2. Modified soybean oil polymers Several types of functionalization can be obtained at various active sites within the triglyceride structure, such as the double bond, the ester group, the allylic carbons, and the carbons a to the ester group. Various chemical pathways for functionalization of these triglycerides have been studied. LaScala and Wool et al. [1] analyzed optimization of the effect of chemical functionalization on the mechanical properties and thermal stability of some resins. The viscoelastic properties of resin samples made of AESO and cured at room temperature with varying amounts of styrene were studied. The 1 H NMR spectra of AESO are shown in Fig. 9. Some triglyceride-based monomers prepared from acrylic acid are shown in Fig. 10. It was found that both E0 and Tg increased with increasing styrene content in the copolymers. The styrene content at 33.3 wt%, or a 2:1 AESO to styrene ratio, was considered optimal ARTICLE IN PRESS Fig. 9. The 1 H NMR spectra of acrylated epoxidized soybean oil (AESO). Reprinted with the permission from J Appl Polym Sci 2001; 82: 710 r John Wiley and Sons, Inc. [1]. Table 7 Shape memory properties of soybean oil polymers Polymer sample Tg (1C) ne (mol/m3 ) Shape memory results (%) D FD R SOY45ST32-DVB15-(NFO5-BFE3) 68 1.8 102 100 80 100 LSS45ST32-DVB15-(NFO5-BFE3) 61 5.3 102 86 96 100 CLS45ST32-DVB15-(NFO5-BFE3) 76 2.2 103 77 98 100 SOY45ST32-(DVB5-NBD5-DCP5)-(NFO5-BFE3) 42 9.8 10 100 63 100 (SOY22.5-LSS22.5)-ST32-(DVB5-NBD5-DCP5)-(NFO5-BFE3) 43 1.3 102 100 74 100 (SOY15-LSS15-CLS15)-ST32-(DVB5-NBD5-DCP5)-(NFO5-BFE3) 44 2.7 102 100 75 100 SOY45ST20-(DVB9-NBD9-DCP9)-(NFO5-BFE3) 68 3.1 102 100 97 100 (SOY22.5-LSS22.5)-ST20-(DVB9-NBD9-DCP9)-(NFO5-BFE3) 70 3.7 102 100 98 100 (SOY15-LSS15-CLS15)-ST20-(DVB9-NBD9-DCP9)-(NFO5-BFE3) 74 5.2 102 100 99 100 Reproduced with permission from Journal of Applied Polymer Science 2002; 84: 1539 r John Wiley and Sons, Ltd., [15]. Tg ¼ Glass transition temperature. ne ¼ Cross-linking density. D ¼ Deformability of the material at temperature higher than Tg. FD ¼ Degree to which the deformation is fixed at ambient temperature. R ¼ Final shape recovery. 992 V. Sharma, P.P. Kundu / Prog. Polym. Sci. 31 (2006) 983–1008
