Blend film

Chitin films can be manufactured from DMAc solutions or by other approaches, for example, blend films of beta-chitin (derived from squid pens) and poly(vinyl alcohol) (PVA) were prepared by a solution casting technique from corresponding solutions of beta-chitin and PVA in concentrated formic acid. Upon evaporation of the solvent, the film having 50/50 composition was found to be cloudy [224]. 

These tactoids are responsible for the particular geometrical structures formation in the blends, which leads to the formation of superstructures in the thickness of the blended film. The Young s modulus of the hybrid is increased by this kind of structural feature. After that, the preparation of intercalated PLA/ OMMT nano-composites with much improved mechanical and thermal properties was reported by Bandyopadhyay et al. (1999). 

Rasal, R.M. and Hirt, D.E. 2008. Toughness decrease of PLA-PHBHHx blend films upon surface-confined photopolymerization. Journal of Biomedical Materials Research Part A 88 1079-1086. 

Agari, Y, Shimada, M., Ueda, A. and Nagai, S. (1996) Preparation, characterization and properties of gradient polymer blends discussion of poly(vinyl chloride)/poly (methyl methacrylate) blend films containing a wide compositional gradient phase. Macromol. Chem. Phys., 197, 2017-2033. 

H Nishino, G Yu, AJ Heeger, T-A Chen, and RD Rieke, Electroluminescence from blend films of poly(3-hexylthiophene) and poly(Y-vinylcarbzaolc), Synth. Met., 68 243-247, 1995. 

C Weder, C Sarwa, C Bastiaansen, and P Smith, Highly polarized luminescence from oriented conjugated polymer/polyethylene blend films, Adv. Mater., 9 1035-1039, 1997. 

ARA Palmans, M Eglin, A Montali, C Weder, and P Smith, Tensile orientation behavior of alkoxy-substituted BA(phenylethynyl)benzene derivatives in polyolefin blend films, Chem. Mater., 12 472-480, 2000. 

PVA and (3-CD evidenced a good compatibility and produce transparent blend films [84],... 

Oxygen and toluene permeability of the blend film decreases as a nonlinear function with increasing the EVOH content, as it may be seen in table 19. 

The EVOH-COOH compatibilizer use determines the increasing of the blend film oxygen permeability that becomes two orders of magnitude higher than that of a coextruded film with the same percentage of EVOH [298], That means that EVOH-COOH acts that an interfacial agent. 

Beagan, C.M., McNally, G.M., and Murphy, W. R., Metallocene Catalysed Polyethylene in Blown Film Applications-A Comparison Between Monoextruded Blended Films and Coextruded Films, SPEANTEC Tech. Papers, 44, 128 (1998)... 

Figure 12.19 Scores and loadings obtained from PCA analysis of the NIR spectra of high-density/hw-denshy polyethylene blend films shown in Figure 12.18 (A) scatter plot of first 2 PC scores, (B) overlayed spectral plot of first two PC loadings. In the scores plot, different symbols are used to denote different blend compositions.

Figure 12.22 The regression coefficient spectrum for the PCR model of high-density polyethylene content in the polyethylene blend films.

C.E. Miller, Use of near-infrared spectroscopy to determine the composition of high-density/low-density polyethylene blend films, Appl. Spectrosc., 47, 222 (1993). 

Karim A, Yurekli K, Meredith C, Amis EJ, Krishnamoorti R (2002) Combinatorial methods for polymer materials science phase behavior of nanocomposite blend films. Polym Eng Sci 42 1836-1840... 

Peesan M, Rujiravanit R, Supaphol P (2003) Characterisation of beta-chitin/poly(vinyl alcohol) blend films. Polym Test 22 381-387... 

Sua J-E, Yuanb XY et al (2010) Properties stability and biodegradation behaviors of soy protein isolate/poly(vinyl alcohol) blend films. Polym Degrad Stab 95 1226-1237... 

Araujo MA, Cunha AM, Mota M (2010) Changes on surface morphology of com starch blend films. J Biomed Mater Res A 94A 720-729... 

Parkinson P, Lloyd-Hughes J, Johnston MB, Herz LM (2008) Efficient generation of charges via below-gap photoexcitation of polymer-fiillerene blend films investigated by terahertz spectroscopy. Phys Rev B 78 115321... 

Ohkita H, Cook S, Astuti Y, Duffy W, Tierney S, Zhang W, Heeney M, McCulloch I, Nelson J, Bradley DDC, Durrant JR (2008) Charge carrier formation in polythiophene/fullerene blend films studied by transient absorption spectroscopy. J Am Chem Soc 130 3030... 

Fig. 4. Effects of phosphoric acid (PA) treatment on the thermo-oxidative stability of PBI and PBI/PEI blend films aged in air at 315 °C...

Using dissolution techniques, it was observed that the 10 and 25% 6F-PAI (ODA-based) could be co-dissolved with PBI using DMAc. Solution blends with PBI-PAI ratios ranging from 20/80 to 80/20, in 20% increments, were visually homogeneous and contained no insoluble materials. At 15-20% solids concentration, these blends were processible and showed no sign of polymer precipitation for at least 24 h. Transparent, apparently miscible, blend films were cast from the solution blends of PBI and 10% 6F-PAI. 

Mechanical property studies of the 10% 6F-PAI and PBI blend films further confirmed the existence of synergistic miscibility between the blend component since the tensile modulus and strength of each corresponding file was either equivalent to or exceeded the simple rule of mixtures (Fig. 11). 

Fig. 11a. Tensile strength of 10% 6F-PAI/PBI blend film, b Modulus of 10% 6F-PAI/PBI blend...

Fig. 3 Relative mass change with time of the QCM sensors featuring MIP-PMMA and NIP-PMMA blend films at 30 °C for sorhed vapours of (a) toluene and (b) 1,4-xylene. At zero time the toluene or 1,4-xylene vapour is passed and at the time of 60 min nitrogen gas is passed (1,1 ) 1,4-xylene-MIP-PMMA, (2, 2 ) toluene-MIP-PMMA, (5,5 ) NIP-PMMA (adapted from [113])...

The inclusion of 5 wt% PCBM [l-(3-methoxycarbonyl)propyl-l-phe-nyl-[6,6]C6i] in the spin-coating solutions resulted in efficient polymer emission quenching for all the polythiophenes studied. The transient absorption spectra of the amorphous poly(541)/PCBM blend film. At 10 ps exhibited an absorption peak around 700 nm, similar to that observed for the poly(541) pristine film. The shape of the transient spectrum varied with time, with the absorption peak shifting from 700 nm at 10 is to 900 nm for time delays >100 (is, demonstrating the formation of two distinct transient species in the blend film. The monoexponential lifetime was t = 8 (is under Ar atmosphere and significantly shortened under 02 atmosphere. Monoexponential phase is therefore assigned to the decay of poly(541) triplet excitons. 

For the polymers poly(541) and poly(539), the observation of polymer triplet formation in the blend films indicates that their triplet energies are below that of PCBM (Er k 1.5 eV), while for poly(540), the observation of PCBM triplet rather than polymer triplet formation in the blend indicates that the poly(540) triplet state lies higher in energy than the PCBM triplet state. 

Table 8.9 A summary of the HDPE/LDPE blend films used to demonstrate exploratory analysis methods...

Figure 8.28 is a scatter plot of the first two rotated PC scores obtained from a PCA analysis of the NIR spectra of polyethylene blend films, after rotation was done to improve interpretability. In this example, it was determined that three PCs were optimal for the PCA model, and the rotated PCs one, two, and three explain 46.67, 49.25, and 2.56% of the variation in the NIR spectra, respectively. Although the higher explained variance of the second rotated PC might seem anomalous based on the criterion that PCA uses explained variance to determine each PC, one must be reminded that these explained variances refer to rotated PCs, rather than the original PCs. There are two interesting things to note about this plot ... 

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