Effects of calcium carbonate as the expanding inhibitor on the structural and mechanical properties of expanded starch/polyvinyl alcohol blends

Wei

Lui³

2005

Packag Technol Sci

Response surface methodology (RSM) was used to analyse the effects of polyvinyl alcohol (PVOH) and calcium carbonate (CaCO3) on the physical and mechanical properties (radial expansion ratio, bulk density, compressibility and spring index) of a biodegradable cushioning extrudate. A rotatable central-composite design (CCD) was used to develop models for the objective responses. The experiments were run at 125 degrees C with a feed rate of 27.8 l/h, screw speed of 215 r.p.m. and die diameter of 3.92 mm. Responses were most affected by changes in PVOH levels and to a lesser extent by CaCO3 levels. Individual contour plots of the different responses were overlaid. An optimum radial expansion ratio of 3.39, bulk density of 0.065 (g/cm(3)), compressibility of 32.27(N), and spring index of 0.906 were identified at 36% PVOH and 5% CaCO3. Copyright (c) 2005 John Wiley & Sons, Ltd

Section: Conditions For Optimum Responsesmentioning

confidence: 97%

Response surface optimization of the feed compositions of biodegradable packaging foams

Wei

Lui³

2005

Packag Technol Sci

“…In fact, Wang et al 23 reported a negative effect of CaCO 3 on expansion in extruded starch foams. The optimum value of radial expansion ratio lies very close to the middle of experimental region.…”

Section: Figure 2 Standard Residuals Between Experimental Values Andmentioning

confidence: 97%

Composition optimization of extruded starch foams using response surface methodology

Lui

2004

Packag Technol Sci

Response surface methodology (RSM) was used to analyse the effect of polyvinyl alcohol (PVA) and calcium carbonate (CaCO3) on the objective attributes (shipping bulk density, radial expansion ratio, compressibility and spring index) of a biodegradable cushioning extrudate. A rotatable central composite design (CCD) was used to develop models for the objective responses. The experiments were run at 105degreesC with a feed rate of 27.8 l/h, screw speed 500 r.p.m. and die diameter 3.92 mm. Responses were most affected by changes in polyvinyl alcohol (PVA) levels and to a lesser extent by calcium carbonate (CaCO3) levels. Individual contour plots of the different responses were overlaid, and regions meeting the optimum shipping bulk density of 6.00 kg/m(3). radial expansion ratio of 3.30, compressibility of 43.71 N, and spring index of 0.91 were identified at the PVA level of 20.23% and the CaCO3 level of 7.89%, respectively. Copyright (C) 2004 John Wiley Sons, Ltd

“…Therefore, much interest lies in blending starch with biodegradable synthetic polymers. [11][12][13][14][15] Poly(vinyl alcohol) (PVOH) is a hydrophilic biodegradable polymer, which is mainly composed of CAC bonds. 6 However, its water solubility is related to its degree of hydrolysis, molecular weight, and the modification while blending with other processing additives, 16 with a maximum value at the degree of hydrolysis of 88%.…”

Section: Introductionmentioning

confidence: 99%

Effects of glycerol and ethylene–acrylic acid on composition optimization of PVOH/starch‐blended biodegradable resin using response surface methodology

J of Applied Polymer Sci

Lui³

et al. 2009

Response surface methodology was used to analyze the effect of glycerol (X 1 ) and ethylene-acrylic acid (EAA) level (X 2 ) on the objective (water solubility index (WSI), water absorption index (WAI), and tensile strength) attributes of a poly(vinyl alcohol) (PVOH)/ starch-blended plastic resin. A rotable central composite design was used to develop models for the objective responses. The experiments were run with different barrel temperatures, such as zone 1: 100 C, zone 2: 100 C, zone 3: 105 C, and zone 4: 105 C, respectively, with a feed rate of 20 g/min and screw speed of 25 rpm. Responses were most affected by changes in glycerol level (X 1 ) and to a lesser extent by EAA level (X 2 ). Individual contour plots of the different responses were overlaid, and regions meeting the optimum WSI of 6.10%, WAI of 5.57 g gel/g dry wt, and tensile strength of 62.14 MPa were identified at the glycerol level of 72.41 mL and the EAA level of 36.03 g, respectively.