scholarly journals Improved Dimensional Stability and Mold Resistance of Bamboo via In Situ Growth of Poly(Hydroxyethyl Methacrylate-N-Isopropyl Acrylamide)

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1584
Author(s):  
Tingsong Liu ◽  
Wenhao Zhang ◽  
Jie Wang ◽  
Yan Zhang ◽  
Hui Wang ◽  
...  
Keyword(s):  
Dimensional Stability ◽  
In Situ Polymerization ◽  
Ammonium Persulfate ◽  
Molar Ratio ◽  
Control Group ◽  
Hydroxyethyl Methacrylate ◽  
In Situ Growth ◽  
Isopropyl Acrylamide ◽  
Mold Resistance

Bamboo is a natural and renewable building material but its application has been limited due to the low dimensional stability and poor durability against mold. In this study, monomers of hydroxyethyl methacrylate (HEMA) and N-isopropyl acrylamide (NIPAM) were impregnated in bamboo to facilitate the in situ growth of poly-HEMA and NIPAM (PHN) copolymer. Prior to that, the effects of different reaction conditions, including the molar ratio of HEMA to NIPAM and their concentrations, the amount of initiator (ammonium persulfate, APS) and crosslinking agents (N,N′-Methylenebisacrylamide (MBA), and glutaric dialdehyde (GA)) on the swelling capacity of PHN were optimized. The formation of PHN was confirmed by using Fourier transform infrared spectroscopy and thermogravimetric analysis, which shows the characteristics peaks of both HEMA and NIPAM, and increased pyrolysis and glass transition temperatures, respectively. After impregnation of PHN pre-polymerization formulation to bamboo, it was observed that PHN filled most of the pits in the bamboo cell wall and formed a tight network. Moreover, the dimensional stability of PHN treated bamboo was significantly improved with an anti-swelling efficiency of 49.4% and 41.7%, respectively, after wetting–drying and soaking–drying cycles. A mold infection rate of 13.5% was observed in PHN-treated bamboo as compared to a 100% infected control group after a 30-day mold resistance test. Combined results indicate that in situ polymerization of HEMA and NIPAM in bamboo is a promising method to develop exterior used bamboo products with enhanced dimensional stability and mold resistance.

In situ polymerization of 2-hydroxyethyl methacrylate (HEMA) and 3-(methacryloxy)propyltrimethoxysilane (MAPTES) in poplar cell wall to enhance its dimensional stability

Holzforschung ◽  
2019 ◽  
Vol 73 (5) ◽  
pp. 469-474 ◽  
Author(s):  
Yaoge Huang ◽  
Gaiyun Li ◽  
Fuxiang Chu
Keyword(s):  
Cell Wall ◽  
Dimensional Stability ◽  
In Situ Polymerization ◽  
Alcoholic Solution ◽  
Hydroxyethyl Methacrylate ◽  
Mass Ratio ◽  
X Ray Diffraction ◽  
Good Solubility ◽  
Modified Wood

Abstract Poplar wood samples (2×2×2 cm3) were vacuum/pressure impregnated in alcoholic solution with 2-hydroxyethyl methacrylate (HEMA) and 3-(methacryloxy)propyltrimethoxysilane (MAPTES) in a mass ratio of 3/1 in the presence of catalytic amounts of azobisisobutyronitrile (AIBN). Because of their good solubility and permeability, the HEMA/MAPTES precursors evenly penetrate the poplar cell wall. The impregnated samples were heated at 75°C for 8 h, followed by a heating period at 103±2°C for 8 h, in the course of which an in situ polymerization occurred in the cell wall. The modified wood was characterized by Fourier transform infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Moreover, the dimensional stability of the modified wood was measured and found to be considerably improved.

Chemical synthesis of nanocomposites via in-situ polymerization of aniline and iodoaniline using exchanged montmorillonite

2020 ◽  
pp. 096739112095406
Author(s):  
Mokhtaria Abbas ◽  
Aicha Hachemaoui ◽  
Ahmed Yahiaoui ◽  
Abdel-Hamid I Mourad ◽  
Abdelkader Belfedal ◽  
...  
Keyword(s):  
In Situ Polymerization ◽  
Ammonium Persulfate ◽  
Molar Ratio ◽  
Molar Ratios ◽  
Transmission Electron ◽  
Diffraction Peaks ◽  
Uv Visible ◽  
Xrd Patterns ◽  
Microscopy Techniques

The focus of this research is to synthesis different nanocomposites by in situ chemical polymerization. The nanocomposites were prepared by intercalating monomers such as aniline, iodoaniline or combination of aniline and 2-iodoaniline into modified montmorillonite clay. The syntheses were carried out using ammonium persulfate as oxidant with different molar ratios of oxidant to monomer. The resulting nanocomposites were investigated and confirmed by X-ray fluorescence spectroscopy, XRD, UV-visible, FTIR spectroscopy, cyclic voltammetry and transmission electron microscopy techniques. XRD patterns show that, the intensity of diffraction peaks for polymers/(M-Na) composites are lower than that for (M-Cu). This is attributed to the interaction of montmorillonite with polyaniline (PANI), polyiodoaniline (PIANI) and poly (ANI- co-2-IANI) molecular chains. The FTIR and UV-vis spectroscopic results also confirmed the presence of iodine in the nanocomposite. When looking at the yield of the process, highest yield is obtained for the poly (ANI- co-IANI) (80:20 molar ratio) and the lowest yield is for PANI/M-Na composite.

scholarly journals ZIF-8 and polyaniline modified coconut gel to fabricate composite aerogel for efficient removal of tetracycline

2020 ◽  
Vol 185 ◽  
pp. 04055
Author(s):  
Qun Liu ◽  
Fanming Zeng ◽  
Xiao Li ◽  
Zhongmin Su
Keyword(s):  
Large Scale ◽  
In Situ Polymerization ◽  
In Situ Growth ◽  
Composite Aerogel ◽  
Composite Adsorbent ◽  
Natural Polysaccharide ◽  
Freeze Dried ◽  
Interface Layers

To overcome the limitations of large-scale applications for MOFs in the powder form, herein, we proposed a strategy of in-situ growth ZIF-8 onto polyaniline (PANI) modified coconut hydrogel (CCH). Firstly, PANI played the role of metal chelated layers, which were coated on CCH by in-situ polymerization. Then, ZIF-8 nanocrystals were in-situ growth on the surface of the PANI coated CCH to synthesise the composite adsorbent ZIF-8/PANI/CCH. Finally, after vacuum freeze-dried, a white and well structured ZIF-8/PANI/CCA(ZIF-8/polyaniline/coconut aerogel) was obtained. The loading mass ratios of ZIF-8 on CCA and PANI/CCA were 11.3% and 37.5%, respectively, which indicates that PANI as interface layers can effectively promote the in-situ growth of ZIF-8. The obtained composite adsorbent (ZIF-8/PANI/CCA) was applied for the adsorption of tetracycline (TC)，and the removal efficiency reaches over 91.6%. This strategy may provide an effective and versatile pathway to increase MOF loading mass on natural polysaccharide aerogel and sequentially branch out their applications in pollutant treatment fields.

In Situ Fabrication of Nanoscale Graphene Oxide/Polyaniline Composite and its Electrochemical Properties

2010 ◽  
Vol 148-149 ◽  
pp. 1547-1550 ◽  
Author(s):  
Hua Lan Wang ◽  
Qing Li Hao ◽  
Xi Feng Xia ◽  
Zhi Jia Wang ◽  
Jiao Tian ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
In Situ Polymerization ◽  
Ammonium Persulfate ◽  
Polymerization Process ◽  
Electrochemical Test ◽  
X Ray ◽  
Transmission Electron

A graphene oxide/polyaniline composite was synthesized by an in situ polymerization process. This product was simply prepared in an ethylene glycol medium, using ammonium persulfate as oxidant in ice bath. The composite was characterized by field emission scanning electron microscopy, transmission electron microscopy, X-Ray photoelectron spectroscopy, Raman spectroscopy and electrochemical test. The composite material showed a good electrochemical performance.

scholarly journals Preparation of Wood-Based Panel Composites with Poplar Veneer as the Surface Layer Modified by In-Situ Polymerization of Active Monomers

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 893 ◽  
Author(s):  
Xiaoyan Yu ◽  
Dandan Xu ◽  
Yan Sun ◽  
Yuran Geng ◽  
Jilong Fan ◽  
...  
Keyword(s):  
Maleic Anhydride ◽  
Hot Pressing ◽  
In Situ Polymerization ◽  
Solid Wood ◽  
Modulus Of Rupture ◽  
Molar Ratio ◽  
Environment Friendly ◽  
Good Surface ◽  
Complex Preparation

Wood-based panels covered by melamine-impregnated paper are widely used in floors and furniture, due to its good surface texture, hardness, wear resistance, and waterproof function. However, there are still some problems, such as formaldehyde release from the impregnated resin, non-wood touch, and complex preparation processes. Therefore, this study designed glycidyl methacrylate (GMA) and ethyleneglycol dimethacrylate (EGDMA), combined with maleic anhydride (MAN) as a reactive catalyst, to build an active monomers system. It was first impregnated into poplar veneers, and then in-situ polymerized within the veneer using a hot pressing process, which realized the gluing of the veneer onto the wood-based panel substrate, synchronously. Such treatment aims to obtain wood-based panel composites decorated by the modified veneer, with real solid wood touch feeling, satisfied surface properties, and environment friendly glue bonding. The results indicated that the optimized reaction ratio of the active monomers (GMA:EGDMA) was 2:1 (molar ratio), and the maleic anhydride addition accounted for 6 wt.% of the total monomers. Under the optimized hot pressing condition, the modified veneer closely bonded to the wood-based panel substrate without obvious interfacial gaps. The hardness, abrasion resistance, modulus of rupture, and water resistance of the composites were significantly improved. Such results indicate that the treatment realized the perfect merging of solid wood touch feeling, environment friendly feature, and excellent properties of the composite. It was highly expected to replace the traditional melamine-impregnated paper to decorate wood-based panels, and could be potentially applied as surface decorating materials in wide areas of desktop, floor, cupboard, wardrobe, and so on.

Properties of Polyaniline with the Doping of Different Acid

2012 ◽  
Vol 502 ◽  
pp. 31-35 ◽  
Author(s):  
Xiao Hua Wang
Keyword(s):  
Thermal Stability ◽  
Reaction Time ◽  
Reaction Temperature ◽  
Acid Content ◽  
In Situ Polymerization ◽  
Ammonium Persulfate ◽  
Dodecylbenzenesulfonic Acid ◽  
Thermal Stability Of

Polyaniline(PANI) with the doping of hydrochloride(HC1), aminosulfonic acid (NH2SO3H) or dodecylbenzenesulfonic acid(DBSA) was prepared by in-situ polymerization. Effects of acid content, reaction time, oxidant ammonium persulfate (APS) dosage and reaction temperature on the conductivity of PANI were studied. The resistance and thermal stability of them were compared. Results show that the largest conductivity of HC1-PANI is 1.98 s.cm-1 among them in case the C(HC1)=0.5mol/L, reaction time is 6.0h, n(APS/aniline)=1.0; The conductivity of NH2SO3H-PANI is 0.2s.cm-1 in case the C(NH2SO3H)=1.0mol/L, reaction time is 6.0h, n(APS/aniline)=2.0; The conductivity of DBSA-PANI is 0.98s.cm-1 in case the C(DBSA)=1.0 mol/L, reaction time is 8.0h, n(APS/aniline) = 2.0. The the least resistance of HC1-PANI is 10Ω, and that of NH2SO3H- PANI is the largest of 120Ω. The order of their thermal stability is DBSA-PANI > NH2SO3H-PANI > HC1-PANI before 350°C, that of their thermal stability is inverse when it reaches 350°C.

scholarly journals Synthesis and Characterization of TNTs/Polyaniline Composite as Photocatalyst Degradation of Rhodamin B by Visible Light

2017 ◽  
Vol 3 (5) ◽  
pp. 41
Author(s):  
Atik Setyani ◽  
Sri Wahyuni ◽  
Sigit Priatmoko ◽  
Emas Agus Prastyo Wibowo ◽  
Nur Amin
Keyword(s):  
Energy Gap ◽  
In Situ Polymerization ◽  
Anatase Phase ◽  
Sol Gel ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Pani Composite ◽  
Stretching Vibration

<p>The purpose of this research is to study the effect of the amount of aniline on their photocatalytic activity. Nano TiO<sub>2</sub> was synthesized using sol-gel method with TiPP precursor. XRD characterization results showed that nano TiO<sub>2</sub> with calcination temperature of 450 °C had size of 13.8 nm with high crystalline. The diffraction peaks of nano TiO<sub>2</sub> at 2θ are 24.45°; 37.075°; 47.26° and 53.18°. Nano TiO<sub>2</sub> was then synthesized with hydrothermal treatment 24 h of 140 °C to produce TNTs. The results of XRD analysis shows anatase phase with field (004) and (200). The morphology of TNTs begins to form at the calcinations temperature of 600 °C with textural coefficient value of 0.998 3 . Synthesis of composite TNTs/PANI (polyaniline) was done by in situ polymerization technique of aniline which was already contained nano TiO<sub>2</sub>. The molar ratio of aniline and APS in the synthesis of a composite is 1:1.5 with the addition of aniline of 15 %; 20 % and 25 % (w/w %). Characterization using FTIR showed the stretching vibration of the C=N in wavelength of 1 600 cm<sup>–1</sup> to mark the formation of quinonoid compounds of polyaniline. The test of the rhodamine B degradation gave the best results on the 25 % TNTs/PANI composite, with the degradation percentage of 58.73 %. The characterization results using dr-uv proved that the decrease of energy gap in the TNTs/PANI composite which as evidenced with Kubelka-Munk calculation equation that was 25 % TNTs/PANI amounting to 3.19 eV and TNTs at 3.24 eV.</p>

scholarly journals Combined Chemical Modification of Bamboo Material Prepared Using Vinyl Acetate and Methyl Methacrylate: Dimensional Stability, Chemical Structure, and Dynamic Mechanical Properties

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1651 ◽  
Author(s):  
Saisai Huang ◽  
Qiufang Jiang ◽  
Bin Yu ◽  
Yujing Nie ◽  
Zhongqing Ma ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Chemical Modification ◽  
Methyl Methacrylate ◽  
Vinyl Acetate ◽  
Dimensional Stability ◽  
Chemical Structure ◽  
In Situ Polymerization ◽  
Dynamic Mechanical Properties

Acetylation and in situ polymerization are two typical chemical modifications that are used to improve the dimensional stability of bamboo. In this work, the combination of chemical modification of vinyl acetate (VA) acetylation and methyl methacrylate (MMA) in situ polymerization of bamboo was employed. Performances of the treated bamboo were evaluated in terms of dimensional stability, wettability, thermal stability, chemical structure, and dynamic mechanical properties. Results show that the performances (dimensional stability, thermal stability, and wettability) of bamboo that was prepared via the combined pretreatment of VA and MMA (VA/MMA-B) were better than those of raw bamboo, VA single-treated bamboo (VA-B), and MMA single-treated bamboo (MMA-B). According to scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analyses, VA and MMA were mainly grafted onto the surface of the cell wall or in the bamboo cell lumen. The antiswelling efficiency and contact angle of VA/MMA-B increased to maximum values of 40.71% and 107.1°, respectively. From thermogravimetric analysis (TG/DTG curves), the highest onset decomposition temperature (277 °C) was observed in VA/MMA-B. From DMA analysis, the storage modulus (E’) of VA/MMA-B increased sharply from 15,057 Pa (untreated bamboo) to 17,909 Pa (single-treated bamboo), and the glass transition temperature was improved from 180 °C (raw bamboo) to 205 °C (single-treated bamboo).

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