Development of high-performance biodegradable rigid polyurethane

Subscriber access provided by WEBSTER UNIV

Biofuels and Biobased Materials

Development of high-performance biodegradable rigid polyurethane foams using full modified soy-based polyols Zheng Fang, Chuanhong Qiu, Dong Ji, Zhao Yang, Ning Zhu, JingJing Meng, Xin Hu, and Kai Guo J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.8b05342 • Publication Date (Web): 06 Feb 2019 Downloaded from http://pubs.acs.org on February 7, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 21

Journal of Agricultural and Food Chemistry

1

Development of high-performance biodegradable rigid polyurethane

2

foams using full modified soy-based polyols

3

Zheng Fanga,†, Chuanhong Qiub,†, Dong Jia, c, Zhao Yangd, Ning Zhua, Jingjing Menga, Xin Hue, Kai Guoa, f,*

4

a. College

5

b. School

of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, PR China.

6

c. Yangzi

Petrochemical Company Ltd., SINOPEC, Nanjing 210048, PR China.

7

d. College

of Engineering, China Pharmaceutical University, Nanjing 210009, PR China.

8

e. College

of Materials Science And Engineering, Nanjing Tech University, Nanjing 211816, PR China.

9

f.

of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China.

State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China.

10

† These two authors contributed equally to this work.

11

Abstract

12

Fossil fuel resources depletion and growing concern about environmental issues have risen demand for newly sustainable

13

biomaterials. To address this challenge, a new type of biodegradable and environmental rigid polyurethane foam named as

14

RPUF-M from full modified soy-based polyols have been synthesized without the addition of petroleum-based polyols. Based

15

on the analysis of structure-activity relationship, a new kind of bio-based polyurethane polyols named as Bio-polyol-M was

16

designed and synthesized directly from epoxidized soybean oil and a novel polyhydroxy compound in a three-step continuous

17

microflow system. In the continuous microflow system, the epoxidation of soybean oil, the synthesis of GLPO and the ring-

18

opening reaction of epoxidized soybean oil were coupled. Another soy-polyol named as Bio-polyol-B was synthesized in Batch

19

mode. In comparison with Bio-polyol-B, Bio-polyol-M had a higher hydroxyl number and a much lower viscosity. Besides, the

20

RPUF-M also possessed a series of advantages over the rigid polyurethane foam named as RPUF-B from Bio-polyol-B

21

KEY WORDS : Soy-polyol, Rigid polyurethane foam, Microflow system.

ACS Paragon Plus Environment


22

Introduction

23

Currently, it is a hot research topic to replace petrochemical base materials with biomass materials.

24

Royal Dutch Shell has estimated that biomass would provide 30% of world’s chemicals and fuels by 2050.

25

Bio-based polyurethane, a green and environmentally-friendly polyurethane, produced by vegetable oil

26

polyols instead of petroleum-based polyols will have a large application prospect. Polyurethanes (PUs),

27

usually prepared from compounds containing two or more reactive hydroxyl groups (diols or polyols)

28

and isocyanates1, are a vital group of polymers which exhibit a versatile range of properties and

29

applications2. In the commercial products made of polyurethane materials, the most important one is

30

rigid polyurethane foams (RPUFs), which have been indispensable materials in refrigeration,

31

transportation, packaging, automotive industry, and building construction3, accounting for about 23% of

32

all polyurethane production on account of the characteristics such as low density, low thermal

33

conductivity, low moisture permeability, and high strength-to-weight ratio.4

34

One of the most serious problems in large-scale production of RPUFs is that they depend on petroleum

35

oil as their raw material for its elementary compositions: hydroxyl-containing polyols5. Currently, fossil

36

fuel resources depletion and growing concern about environmental issues have led researchers to pay

37

more attention to the preparation of RPUFs from renewable resources6. In these bio-renewable

38

feedstocks, vegetable oil is a kind of annually renewable natural material which was cheap and obtained

39

easily, therefore it have shown excellent potential as renewable raw material in the production RPUFs 7.

40

However, it was difficult for almost all these vegetable oil-based polyols commercially available to foam

41

independently without the adding petroleum-based polyols, due to their low hydroxyl number and high

42

viscosity, which make the corresponding foaming material have a number of disadvantages, for instance,

43

high processing difficulty, poor mechanical property, and poor stability (Figure 1). As it was reported in


Page 2 of 21

Page 3 of 21


44

the published literature, the preparation of bio-based RPUFs based on the isocyanate route required

45

more than 50 percent of petrochemical polyether polyols8 or other enhancing components9 such as

46

cellulose microfibers, nanoclays, rice husk ash and etc.. Therefore, development of high-quality

47

biodegradable rigid polyurethane foams using 100% high quality vegetable oil-based polyols is urgently

48

needed. Previous work: Petroleum-based polyols or other enhancing components

Chemically modified

Vegetable oil

Foaming

Vegetable oil-based polyols

Rigid polyurethane foams

Our work: EpoxidatioHydroxylation

Foaming

Microreaction technology Soybean oil

Soybean oil-based polyol

a novel soy-based polyol

49

Rigid polyurethane foams

green synthetic method in microflow system

RPUFs synthesized from 100% modified soy-based polyol

50

Figure 1. Synthesis of RPUFs from vegetable-based polyols.

51

Soybean oil, composed of triglyceride molecules containing unsaturated fatty acids, has been most

52

valuable as starting material for polyol conversion due to its several advantages compared to other

53

vegetables oils, such as volume stability, price stability and versatility for chemical modification10. The

54

soy-based polyols are usually obtained by the following method: hydroformylation, transesterification,

55

epoxidation followed by hydroxylation, or ozonolysis followed by hydrogenation.11

56

The method we chose in this study was Epoxidation-Hydroxylation, for it was effective to introduce a

57

vicinal secondary alcohol via epoxidation of double bonds in unsaturated fatty acids, subsequently

58

nucleophilic ring opening of the epoxide group chains(Scheme 1). Several literatures have reported the



Page 4 of 21

59

synthesis of soy-based polyols by this method12 and corresponding commercial products prepared by

60

this method have become available5. However, these synthesis methods have many problems. For

61

example, the dangling chains, as a result of saturated fatty acids, act as plasticisers that reduce the PU

62

rigidity and lower the glass-transition temperature13. Besides, reacting in conventional flasks can cause

63

some problems, such as increased risks from peroxide and long reaction time. Beyond that, the

64

ineluctable oligomeric side reaction would consumed newly generated hydroxyl groups, which resulted

65

in lower hydroxyl numbers and higher viscosities of polyols , and all these characteristics above were not

66

unfavorable for RPUF preparation14. While researchers have made several advancements, such as

67

increasing PU rigidity with introducing phenyl ring to the polyol structure15 and modifying the foams with

68

addition of lignin16, rice husk ash9b, cellulose microfibers and nanoclays9a, it was also difficult for the soy-

69

based polyols to foam without the addition of petroleum-based polyols. O O R1

O n

O O O

R1

R2

O

Soybean oil

n

O

m

O O

Epoxidation

O

O

O

O

m

R1

RH

O

OH

OH O

RH :

OH

O O

+

70

R2

O n

m

O O

m

Soy-based polyols O

R1

R

O

O

R2

Epoxidized soybean oil

Our Work:

O O

Hydroxylation

O

OH n

Side reaction (Oligomerisation)

O R2

OH

OH OH OH

O

R

71

Scheme 1. Synthesis of soy-based polyols.

72

Micro reaction technology, a new method in chemical synthesis, has attracted much attention over

73

traditional batch chemistry. Based on process intensification, excellent heat and mass transferensures,

74

reactions are completed quickly and efficiently with less energy consumption. Thus, the accurate control

75

of the reaction process is ensured, and the side effects are greatly reduced. In addition, other

76

advantages such as operational safety, extremely fast mixing, and precise residence time control, also


Page 5 of 21


77

help it garner positive responses from researchers.17 In order to solve some problems in traditional

78

synthetic methods, we used a continuous micro-flow system in this study. Through microreaction,

79

vegetable oil-based polyols were synthesized rapidly and efficiently. In previous study, our research

80

group have synthesised a variety of high quality epoxidized soybean oil by a continuous micro-flow

81

system, which laid a foundation for developing high-quality polyols. The results show that microreaction

82

technology is advantageous to the preparation of high-quality polyols.18

83

In this study, in order to improve all sorts of the defects brought by conventional polyols, phenyl group

84

were introduced into the polyol structure, accordingly, a novel polyhydroxy compound labeled GLPO was

85

synthesized based on the equimolar reaction of glycerine with styrene oxide. GLPO, which was designed

86

to reduce the cross-linking and guarantee a certain hydroxyl value, only had one primary hydroxyl group.

87

At the same time, the epoxidized soybean oil was obtained by the epoxidation of soybean oil; then,

88

GLPO was involved in the ring-opening with epoxidised soybean oil. Both of the three-part operations

89

are completed in a continuous microflow system. By optimization of the reaction parameters, a polyol

90

product with higher hydroxyl number and moderate viscosity was obtained. Furthermore, the

91

corresponding RPUFs were also prepared for the evaluation of the effect of soy-based polyols on the

92

performance of foams. In order to characterize the samples, several test experiments were conducted.

93

The experiment items mainly included fourier transform infrared (FTIR), scanning electron microscopy

94

(SEM), dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA).

95

Meterials and method

96

Reagents



97

All reagents used in this study were from commercial suppliers and were used without further

98

processing unless otherwise stated.

99

Preparation of soy-polyol in micro-flow system

100

The process in microflow system included three parts: the epoxidation of soybean oil, styrene oxide

101

reacting with glycerine simultaneously, and finally the hydroxylation of epoxidised soybean oil (ESO) with

102

synthesized polyols (GLPO). The complete flow chart was showed in Scheme 2. Our group has reported

103

the preparation of epoxidized soybean oil earlier19, and this mature synthesis method was directly

104

adopted in this research. The concrete proportion, flow velocity, residence time and reaction

105

temperature of the stock in the pump I and the pump II were referred to the previous literature.18b

106

Meanwhile, in the other two plunger pumps, the flow velocity of styrene oxide in the pump III was

107

3.2mL/min, and the other mixture containing glycerine and potassium hydroxide in the pump IV had a

108

flow velocity of 3.5 mL/min. In the microreactor B, the residence time was 5min and reaction

109

temperature was set to 130°C. Next, the synthesized GLPO were mixed with ESO and transferred into the

110

microreactor C. Finally, the mixed compounds were held for 8 min at 75°C. After the stratification of oil-

111

water separator, the oil phase (soy-polyol ) was collected while the aqueous phase was expelled.

112

In the last step of hydroxylation procedure, the sulfuric acid remained during the epoxidation procedure

113

was used as a catalyst and ring-opener. The obtained crude soy-polyol was posttreated according to the

114

method described in the literature. 18b The purified soy-polyol was named as Bio-polyol-M

115

Table 1. Rigid polyurethane foam formulation.


Page 6 of 21

Page 7 of 21


Ingredients

Formulation

soy-

AK-

polyol

8803

100

2.0

cyclopentane

Polycat®8

H2O

Polycat®41

KAc solution (30 wt %)

13

2.6

1.2

1.0

0.1

(parts by weight) I Soybean oil

O

Aqueous phase

Mixer

II

H2O2/HCOOH H2SO4(5wt%) EDTA-2Na(3wt%)

A

Epoxidized Soybean oil Mixer

III

OH

OH OH + KOH OH

C

OH O

OH

Oil-water Separator

Mixer

IV

B Soy-based polyols Pump

116

Sandwich Microreactor

117

Scheme 2. Schematic diagram of soy-polyol preparation process.

118

Preparation of GLPO in batch mode

119

The GLPO in batch mode was synthesized as follows: 35.46g (0.38mol) glycerine and 0.53g potassium

120

hydroxide was added into a 500mL flask and stirred at 75°C till potassium hydroxide was totally

121

dissolved. Then 42g (0.35mol) styrene oxide was slowly dripped at 130°C and continued reacting for

122

10hous. After reaction, the reaction mixture was poured into a separatory funnel when it is hot. The

123

crude product was washed successively with dilute hydrochloric acid and saturated salt water until the

124

water phase had a pH of 6.0. Then, the organic solvent in the crude product was evaporated, and further

125

purified by porous resin adsorption method.

126

Preparation of soy-polyol in batch mode

127

The soy-polyol in batch mode was synthesized as follows: 19.24g commercially available ESO, 21.76g

128

GLPO, and 0.60mL concentrated sulfuric acid were added into a 500mL flask, stirred at 65°C and reacted



129

for 12h. After the reaction solution was cooled to 25°C, the aqueous phase was separated. The further

130

post-treatment was consistent with the method mentioned above, and corresponding soy-polyol named

131

as Bio-polyol-B was finaly obtained.

132

Preparation of rigid polyurethane foam

133

The foaming process was based on the literature reported previously.18 On the basis of the formulation

134

in Table 1, the RPUFs were prepared using the method of free-rise foaming. As per the kind of soy-polyol

135

uesd in the foaming process, the foams were named as RPUF-M and RPUF-B, respectively.

136

Results and discussion

137

In the case of hydroxylation, oligomerization is inevitable.21 Thus, the experimental hydroxyl numbers

138

were inconsistent with the theoretical hydroxyl numbers.18b In the microflow system, the optimization of

139

hydroxylation process was carried out by studied the effect of variation of reaction condition on the

140

hydroxyl number and the epoxy content of soy-polyols, namely, the variation of potassium hydroxide

141

concentration, residence time, and temperature, as shown in Figures 2(a), (b) and (c).

142

Effect of the potassium hydroxide concentration on performance of soy-polyol in micro-flow system

143

In this research, sulfuric acid was selected as the catalyst in situ epoxide ring-opening for economic and

144

security reasons. In the three-part continuous flow reaction, sulfuric acid was involved in the catalysis of

145

two-part of the reaction,which respectively were the epoxidation of soybean oil and the hydroxylation of

146

ESO. Because no sulfuric acid was added in the last step, the amount of potassium hydroxide in the

147

synthesis of GLPO was crucial, too much or too little could affect the reaction. The reaction temperature

148

of microreactor C was 65°C and the residence time of ESO ring-opening was 10min as the initial reaction

149

conditions in the microflow system.


Page 8 of 21

Page 9 of 21


150

151 152

Figure 2. (a), (b) and (c) are effects of potassium hydroxide concentration, residence time and reaction

153

temperature on the soy-polyols performance, respectively.

154

As illustrated in Figure 2(a), with the increase of potassium hydroxide, the epoxy content rose after

155

showing the first fall trend, while the change of hydroxyl number was opposite, which peaked at a

156

dosage of 1.8wt %. It was not hard to understand that moderate concentration of potassium hydroxide

157

could catalyzed the synthesis of GLPO efficiently, as well as neutralize part of sulphuric acid. However,

158

overmuch potassium hydroxide consumed excess sulphuric acid, thus affected the next hydroxylation. A

159

large amount of sulfuric acid could greatly shorten the time for the ring opening reaction.21

160

Simultaneously, as the sulfuric acid concentration increased, the oligomerization reaction was also

161

enhanced, for the reaction rate of oligomeric ether formation is first-order under concentrated acid

162

conditions.22



163

Effect of residence time on performance of soy-polyol in micro-flow system

164

The concentration of potassium hydroxide was 1.8wt % and the reaction temperature of microreactor C

165

was 65°C as the initial reaction conditions. By adjusting the volume of the microreactor, the residence

166

time was changed from 4min to 14min. As it was shown in Figure 2(b), with the extension of the

167

residence time, the epoxy content tended to decrease first and then rise, which was opposite to that of

168

hydroxyl number. It is not hard to understand that the residence time was too short to complete the

169

reaction, therefore, the epoxy content decreased in a short time. In this research, the hydroxylation

170

process was a solvent-free reaction, due to its heterogeneity, it relied heavily on the high mass transfer

171

efficiency of microreactors.18 Much longer residence time requires larger microreactors, which

172

weakened the mass transfer efficiency, therefore, the epoxy content eventually increased.

173

Effect of temperature on performance of soy-polyol in micro-flow system

174

According to the optimized reaction conditions above, the optimal concentration of potassium hydroxide

175

was 1.8wt % and the optimal residence time was 8min. To explore the effects of temperature, a

176

temperature gradient from 45°C to 95°C was taken. As it was shown in Figure 2(c), with the temperature

177

gradually increased, the hydroxyl number increased first and then dropped slightly, while the epoxy

178

content decreased. Just as anticipated, higher temperatures reduced the viscosity of oil, and made

179

mixture more compatible. In spite of the epoxy and ring-opening reactions are exothermic process, with

180

the increase of temperature, the reaction rates of oligomerization and ring-opening were all accelerated.

181

When the temperature reached 85°C, the soy-polyol had the highest hydroxyl number of 319mg KOH/g,

182

at the same time, the epoxy content was 0.20%, and the viscosity was 9765mPa·s. However, when the

183

temperature was 75°C, the hydroxyl number of soy-polyol synthesised was sightly reduced to 315mg

184

KOH/g, but it had a significantly lower viscosity of 7048mPa·s, as well as a higher epoxy content of 0.51%.


Page 10 of 21

Page 11 of 21


185

In consideration of lower energy and viscosity, the optimal reaction temperature was set at 75°C. The

186

soy-polyol obtained under the optimal conditions was named as Bio-polyol-M.

187

Characterization of soy-polyols properties

188

Figure 3 showed the FTIR spectra of the Bio-polyo-B and Bio-polyol-M. As it can be seen from the figure

189

3, the peak at 757 cm-1 corresponded to –CH out-of-plane bending vibrations in aromatic ring. To Bio-

190

polyol-M, the hydroxyl peak enhancement at 3420 cm-1 demonstrated that Bio-polyol-M contained much

191

more hydroxyl groups, which was consistent with the experimental data in Table 2. Additionally, the Bio-

192

polyol-M peak at 913 cm-1 corresponded to the epoxy group which indicated Bio-polyol-M had a higher

193

epoxy content.

194 195

Figure 3. FTIR spectra of Bio-polyol-M and Bio-polyol-B.

196

As shown in Table 2, compared with Bio-polyol-M, Bio-polyol-B, had a higher visocity and a lower

197

hydroxyl number, which indicated that oligomerization was more likely to occurred in the batch mode.

Hydroxyl number

Acid number

Epoxy content

Viscosity

(mg KOH/g)

(mg KOH/g)

(%)

(mPa▪s)

Bio-polyol-M

315

1.37

0.51

7048

Bio-polyol-B

219

1.25

0.19

23054

polyol

198

Table 2. General properties of Bio-polyol-M and Bio-polyol-B.



199

Properties of soy-based rigid polyurethane foams

200

Figure 4 showed the cross-sectional SEM images of RPUF-M and RPUF-B. As was shown in the images, no

201

matter what type of polyol, they all possessed closed-cell structures. It can be seen from the SEM image

202

of RPUF-M that the cell size was approximate hexagon and relatively uniform, and most cells were

203

complete and closed. In contrast, RPUF-B had more broken cells and the cell structures were not so

204

uniform. Viscosity of soy-polyol is a crucial factor during the foam cell structure formation. Higher

205

viscosity of soy-polyol would make difficulties in mixing foam ingredients, as well as had an effect on the

206

formation and distribution of the foam cells.16a, 23 Irregular cell structures and the increase of broken cells

207

led to the change of the cell morphology, which was caused by the higher viscosity of polyol which

208

affecting the process of cell nucleation.

209 210

Figure 4. (a),(b) are SEM images of RPUF-M and RPUF-B, respectively.

211

The properties of RPUF-M and RPUF-B were summed up in the Table 3. In comparison with RPUF-B,

212

RPUF-M possessed higher compression strength and density. For RPUFs, the morphology and density of

213

foams will have a certain effect on the compressive strength of them.24 In this study, the specific

214

compression strength was used to analyze the factors that affected the foam compression strength


Page 12 of 21

Page 13 of 21


215

accurately. In comparison with RPUF-B, RPUF-M possessed a higher specific compression strength, this

216

might be a result of its uniform cell structure.

217

Table 3. Properties of RPUF-M and RPUF-B.

foam

a

Density

Compression strength

Specific compression strength (kPa

k value

(kg/m3)

▪m3/kg) a

(kPa)

(mW/(m ▪K))

RPUF-M

34.1

199

5.84

20.2

RPUF-B

35.5

149

4.20

24.6

the ratio of “compression strength” to “density”

218

k value is acrucial parameter for RPUFs, which is positively correlated with average cell size and foam

219

density, and negatively correlated with closed-cell content.8 According to Table 3, it can be seen

220

intuitively, RPUF-M possessed a much lower k value, largely because of its smaller foam density, uniform

221

and smaller cell size, as well as the higher closed-cell content.

222

Additionally, dimensional stability is another significant parameter. As it was shown in Table 4, for both

223

RPUF-M and RPUF-B, the changes of dimension comformed to standard specifications (3% according to

224

the literature24b).

Dimensional stability (%)

Thermal character T5%

T10%

T50%

800 °C

Tg (°C

(°C )

(°C )

(°C )

(residual/%)

)

-0.39

245.6

277.2

334.7

12.68

197.5

-0.82

216.2

234.5

300.7

2.34

194.9

foam

length

width

thickness

RPUF-M

0.29

0.28

RPUF-B

0.65

0.63

225

Table 4. Dimensional stability and thermal properties of RPUF-M and RPUF-B.

226

Figure 5(a) showed the TGA weight loss curves of RPUF-M and RPUF-B, and Table 4 summarized the

227

corresponding data. The decomposition of rigid polyurethane foams includes the dissociation of

228

urethane bonds, the decomposition of soft polyol segments and the further decomposition of segment

229

fragments.25 Within the range of 150°C, the two foams both exhibited slight weight losses because of the



230

evaporation of water. As the temperature increased, in the temperature range of 150°C to 800°C , RPUF-

231

M showsd better thermal stability than RPUF-B .

232 233

Figure 5. (a) TGA weight loss curves of RPUF-M and RPUF-B , (b) Tan δ vs temperature of RPUF-M and

234

RPUF-B.

235

Tan δ was directly tested through DMA, and the glasstransition temperature (Tg) was calculated from the

236

measured data. As can be seen from Table 4 and Figure 5(b), RPUF-M had a higher Tg as a result of its

237

greater cross-linking degree.

238

Conclusions

239

In this study, a green and novel soy-polyol named as Bio-polyol-M was successfully synthesized using a

240

three-step continuous microflow system and the reaction conditions were optimized. In addition,

241

another soy-polyol named as Bio-polyol-B was synthesized in batch mode. Based on the analysis of

242

structure-activity relationship, polyhydroxy was introduced into the oil structure. As a result, the

243

performance of the products has been greatly improved. In comparison with Bio-polyol-B, Bio-polyol-M

244

had a higher hydroxyl number and a much lower viscosity attributed to fewer oligomerization occurred

245

in the microflow system. Furthermore, the corresponding soy-based RPUFs named as RPUF-M and RPUF-

246

B, respectively, were successfully prepared and petrochemical polyols were completely replaced by soy-


Page 14 of 21

Page 15 of 21


247

polyols during the preparation process, and PU-m also possessed a series of advantages, such as higher

248

compression strength, lower k value ,better dimensional stability, slightly higher Tg, and great thermal

249

stability. The experimental results show that continuous microflow system is green and efficient for the

250

synthesis of high-performance soy-polyols.

251

Conflicts of interest

252

There are no conflicts to declare.

253

Acknowledgements

254

The research has been supported by the National Key Research and Development Program of China

255

(2016YFB0301501); The National Natural Science Foundation of China (21776130); The Jiangsu

256

Synergetic Innovation Center for Advanced Bio-Manufacture (XTD1821 and XTD1802); The Top notch

257

Academic Programs Project of Jangsu Higher Education Institutions.

258

Notes and references

259

1

260 261

Chen, R.; Zhang, C.; Kessler, M. R. Polyols and polyurethanes prepared from epoxidized soybean oil ringopened by polyhydroxy fatty acids with varying oh numbers. J. Appl. Polym. Sci. 2014, 132, 1-10.

2

a) Xu, J.; Jiang, J.; Hse, C.Y.; Shupe, T.F. Preparation of polyurethane foams using fractionated products in

262

liquefied wood. J. Appl. Polym. Sci. 2014, 131, 1-7;

263

b) Cinelli, P.; Anguillesi, I.; Lazzeri, A. Green synthesis of flexible polyurethane foams from liquefied lignin.

264

Eur. Polym. J. 2013, 49, 1174-1184;

265

c) Petrovic, Z. Polyurethanes from vegetable oils. Polym. Rev. 2008, 48, 109-155.



266

3

a) Nikje, M. M. A.; Noruzian, M.; Moghaddam, S. T. Investigation of Fe3O4/AEAP supermagnetic

267

nanoparticles on the morphological, thermal and magnetite behavior of polyurethane rigid foam

268

nanocomposites. Polimery/Polymers 2015, 60, 26-32;

269

b) Badri, K. H.; Ahmad, S. H.; Zakaria, S. Production of a high-functionality RBD palm kernel oil-based

270

polyester polyol. J. Appl. Polym. Sci. 2001, 81, 384-389;

271

c) Chian, K. S.; Gan, L. H. Development of a rigid polyurethane foam from palm oil. J. Appl. Polym. Sci.

272

1998, 68, 509-515.

273

4

274 275

Polyol. Polymer (Guildf) 2011, 52, 2840-2846. 5

276 277

Tan, S.; Abraham, T.; Ference, D.; MacOsko, C. W. Rigid polyurethane foams from a soybean oil-based

Desroches, M.; Escouvois, M.; Auvergne, R.; Caillol, S.; Boutevin, B. Fromvegetable oils to polyurethanes: synthetic routes to polyols and mainindustrial products. Polym. Rev. 2012, 52, 38-79.

6

a)Aranguren, M. I.; González, J. F.; Mosiewicki, M. A. Biodegradation of avegetable oil based polyurethane

278

and wood flour composites. Polym. Test. 2012, 31,7-15;

279

b) Yuan, Z.; Mahmood, N.; Schmidt, J.; Tymchyshyn M.;Xu, C. Hydrolytic liquefaction of hydrolysis lignin

280

for the preparation of bio-based rigid polyurethane foam. Green Chem. 2016, 18, 2385-2398.

281

7 a) Sharma, V.; Kundu, P. P. Addition polymers from natural oils-a review. Prog. Polym. Sci. 2006, 31, 983-

282

1008;

283

b) Lebarbé, T.; Maisonneuve, L.; Nguyen, T. H.; Gadenne, B.; Alfos, C.; Cramail, H. Methyl 10-undecenoate

284

as a raw material for the synthesis of renewable semi-crystalline polyesters and poly(ester-amide)s.

285 286

Polym. Chem. 2012, 3, 2842-2851;


Page 16 of 21

Page 17 of 21


287

c) Güner, F.; Yaǧci, Y.; Tuncer Erciyes, A. Polymers from triglyceride oils. Prog. Polym. Sci. 2006, 31,

288

633670.

289

d) Xia Y.; Larock, R. C. Vegetable oil-based polymeric materials: synthesis, properties, and applications.

290

Green Chem. 2010, 12, 1893-1909.

291

8 a) Septevani, A. A.; Evans, D. A. C.; Chaleat, C.; Martin, D. J.; Annamalai, P. K. A systematic study

292

substituting polyether polyol with palm kernel oil based polyester polyol in rigid polyurethane foam. Ind.

293

Crop. Prod. 2015, 66, 16-26;

294

b) Fan, H.; Tekeei, A.; Suppes G. J.; Hsieh, F. H. Rigid polyurethane foams made from high viscosity soy

295

polyols. J. Appl. Polym. Sci. 2013, 127, 1623-1629;

296

c) Tu, Y. C.; Fan, H.; Suppes, G. J.; Hsieh, F. H. Physical properties of water-blown rigid polyurethane foams

297

containing epoxidized soybean oil in different isocyanate indices. J. Appl. Polym. Sci. 2009, 114, 2577-

298

2583;

299

d) Tu, Y. C.; Suppes G. J.; Hsieh, F. H. Water-blown rigid and flexible polyurethane foams containing

300

epoxidized soybean oil triglycerides. J. Appl. Polym. Sci. 2008, 109, 537-544;

301

e) Tu, Y. C.; Kiatsimkul, P.; Suppes, G.; Hsieh, F. H. Physical properties of water-blown rigid polyurethane

302

foams from vegetable oil-based polyols. J. Appl. Polym. Sci. 2007, 105, 453-459.

303

9

a) Zhu, M.; Bandyopadhyay-Ghosh, S.; Khazabi, M.; Cai, H.; Correa C.; Sain, M. Reinforcement of soy

304

polyol-based rigid polyurethane foams by cellulose microfibers and nanoclays. J. Appl. Polym. Sci. 2012,

305

124, 4702-4710;

306

b) da Silva, V. R.; Mosiewicki, M. A.; Yoshida, M. I.; da Silva, M.C.; Stefani P.M.; Marcovich, N.E.

307

Polyurethane foams based on modified tung oil and reinforced with rice husk ash I: Synthesis and physical

308

chemical characterization. Polym. Test. 2013, 32, 438-445;



309

10 a) Lligadas, G.; Ronda, J. C.; Galià, M.; Cádiz, V. Plant oils as platform chemicalsfor polyurethane synthesis:

310

current state-of-the-art. Biomacromolecules 2010, 11, 2825-2835;

311

b) Zhang, C.; Xia, Y.; Chen, R.; Huh, S.; Johnston P. A.; Kessler, M. R. Soy-castor oil based polyols prepared

312

using a solvent-free and catalyst-free method and polyurethanes therefrom. Green Chem. 2013, 15, 1477-

313

1484.

314 315 316

11 Prociak, A.; Rojek, P.; Pawlik, H. Flexible polyurethane foams modified withnatural oil based polyols. J. Cell. Plast. 2012, 48, 489-499. 12 a) Guo, A.; Javni, I.; Petrovic, Z. Rigid polyurethane foams based on soybean oil. J. Appl. Polym. Sci. 2000,

317

77, 467–473;

318

b) Bandyopadhyay-Ghosh, S.; Ghosh, S. B.; Sain, M. Synthesis of soy-polyol bytwo step continuous route

319

and development of soy-based polyurethane foam. J. Polym. Environ. 2010, 18, 437-442;

320

c) Yang, L. T.; Zhao, C. S.; Dai, C. L.; Fu, L. Y.; Lin, S. Q. Thermal and mechanicalproperties of polyurethane

321

rigid foam based on epoxidized soybean oil. J.Polym. Environ. 2012, 20, 230-236;

322

d) Prociak, A.; Rojek, P.; Pawlik, H. Flexible polyurethane foams modified withnatural oil based polyols. J.

323

Cell. Plast. 2012, 48, 489-499;

324

e) Pawlik, H.; Prociak, A. Influence of palm oil-based polyol on the properties offlexible polyurethane

325

foams. J. Polym. Environ. 2012, 20, 438-445.

326

13 a) Lin, B.; Yang, L.; Dai, H.; Yi, A. Kinetic studies on oxirane cleavage of epoxidized soybean oil by methanol

327

and characterization of polyols. J. Am. OilChem. Soc. 2008, 85, 113-117;

328

b) Zlatanić, A.; Lava, C.; Zhang, W.; Petrović, Z. S. Effect of structure onproperties of polyols and

329

polyurethanes based on different vegetable oils. J. Appl. Polym. Sci. 2004, 42, 809-819;

330

c) Petrović, Z. S.; Yang, L.; Zlatanić, A.; Zhang, W.; Javni, I. Network structure andproperties of


Page 18 of 21

Page 19 of 21

331 332 333 334 335 336


polyurethanes from soybean oil. J. Appl. Polym. Sci. 2007, 105, 2717-2727; 14 Rojek, P.; Prociak, A. Effect of different rapeseed-oil-based polyols on mechanical properties of flexible polyurethane foams. J. Appl. Polym. Sci. 2012, 125, 2936-2945. 15 Dumont, M. J.; Kong, X.; Narine, S. S. Polyurethanes from benzene polyolssynthesized from vegetable oils: dependence of physical properties onstructure. J. Appl. Polym. Sci. 2010,117, 3196-3203. 16 a) Luo, X.; Mohanty, A.; Misra, M. Lignin as a reactive reinforcing filler forwater-blown rigid biofoam

337

composites from soy oil-based polyurethane. Ind.Crop. Prod. 2013, 47, 13-19;

338

b) Luo X.; Xiao, Y.; Wu, Q.; Zeng, J. Development of high-performance biodegradable rigid polyurethane

339

foams using all bioresource-based polyols: Lignin and soy oil-derived polyols. International Journal of

340

Biological Macromolecules 2018, 115, 786-791.

341

17 a) Fukuyama, T.; Totoki T.; Ryu, I. Carbonylation in microflow: close encounters of CO and reactive

342

species. Green Chem. 2014, 16, 2042-2050;

343

b) Amii, H.; Nagaki A.; Yoshida, J. low microreactor synthesis in organo-fluorine chemistry. Beilstein J. Org.

344

Chem. 2013, 9, 2793-2802.

345

18 a) Fang, Z.; Yang, Z.; Ji, D.; Zhu, N.; Li, X.; Wan, L.; Zhang K.; K. Guo, K. Novel synthesis of a soy-based polyol

346

for a polyurethane rigid foam. RSC Adv. 2016, 6, 90771-90776;

347

b) Ji, D.; Fang, Z.; He, W.; Zhang, K.; Luo, Z.; Wang T.; Guo, K. Synthesis of soy-polyols using a continuous

348

microflow system and preparation of soy-based polyurethane rigid foams. ACS Sustain. Chem. Eng. 2015,

349

3, 1197-1204.

350

19 He, W.; Fang, Z.; Ji, D.; Chen, K.; Wan, Z.; Li, X.; Gan, H.; Tang, S.; Zhang K.; Guo, K. Epoxidation of soybean

351

oil by continuous micro-flow system with continuous separation. Org. Process Res. Dev. 2013, 17, 1137-

352

1141.



353 354 355 356

20 Zhu, X. Determination of hydroxyl value of epoxy-containing polyester by acetyl chloride method. Chem. Propell. Polym. Mater. 2007, 5, 65-66. 21 Guo, Y.; Hardesty, J. H.; Mannari, V. M.; Massingill, J. L. Hydrolysis of epoxidized soybean oil in the presence of phosphoric acid. J. Am. Oil Chem. Soc. 2007, 84, 929-935.

357

22 Wu, S.; Soucek, M. D. Oligomerization mechanism of cyclohexene oxide. Polymer 1998, 39, 3583-3586.

358

23 Pan, X.; Saddler, J. N. Effect of replacing polyol by organosolv and kraft lignin on the property and structure

359 360

of rigid polyurethane foam. Biotechnol. Biofuels 2013, 6, 12-22. 24 a) Gu, R.; Konar, S.; Sain, M. Preparation and characterization of sustainable polyurethane foams from

361

soybean oils. J. Am. Oil Chem.Soc. 2012, 89, 2103-2111;

362

b) Lee, S.; Ooi, T. L.; Chuah, C. H.; Ahmad, S. Rigid polyurethane foam production from palm oil-based

363

epoxidized diethanolamides. J. Am. Oil Chem. Soc. 2007, 84, 1161-1167.

364 365

25 Zhang, C.; Ding, R.; Kessler, M. R. Reduction of epoxidized vegetable oils: a novel method to prepare biobased polyols for polyurethanes. Macromol. Rapid Commun. 2014, 35, 1068-1074.

366


Page 20 of 21

Page 21 of 21


A novel route to produce high-quality soy-based polyol by using a three-step continuous microflow system was reported and high-performance biodegradable rigid polyurethane foam from full modified soy-based polyols was synthesized without the addition of petroleum-based polyols 80x39mm (220 x 220 DPI)


Development of high-performance biodegradable rigid polyurethane

Recommend Documents