Matrix crystallinity

Rubber content M -matrix M -matrix MWD-matrix Crystallinity... 

In ARP pretreatment of hybrid poplar, deUgnification is increased with the treatment severity, but xylan removal occurs only to a certain extent. Increase of temperature from 175 to 195 °C in ARP does not affect xylan/lignin removal in hybrid poplar, yet the glucan digestibility of treated solid is increased. This is caused by an increase of cellulase accessibility to cellulose created by breakage of certain bonds and reconfiguration of the components in hemicellulose-lignin matrix. Crystallinity index of hybrid poplar increases after the ARP treatment. It is primarily caused by the removal of amorphous components,... 

The chemical structure of an encapsulated molecule is an important parameter that can influence the partition coefficient and then the controlled release into a food. Alcohols and short-chained esters had higher partition coefficients in the oil/polymer system, than in the water/polymer system. Several studies have attempted to model the relationship between the encapsulated molecule, the composition of the food, and the partition coefficient (Arab Tehrany and Desobry 2004). It is also known that matrix crystallinity and glass transition of the matrix are key factors for an efficient controlled release of an active compound. A controlled transition from glassy to rubbery state (temperature, water activity) leads to the best system for good food preservation. A lot of work stiU has to be done to allow perfect control of an active compound release. 

Apart from the Tc, the crystallinity of PP has also been increased by the addition of nanofillers (Bilotti et al., 2008). The Yoimg s modulus of the composites has been reported to increase with polymer matrix crystallinity in the work of Coleman et al. (Coleman et al., 2004). Similar results were also shown in other studies that changes in the crystallinity and the... 

Hydrolytically degradable rubbers (i.e., poly( -CL/L-lac), polytrimethylene carbonate (PTMC), and poly(TMC/ -CL)) were synthesized and solution blended with PLA [204]. Due to differences in the Fedors solubility parameters—PLA 22.75 J° /cm PTMC 21.47 J° /cm poly(TMC/ -CL) rubber 21.09 J° /cm , and poly( -CL/L-lac) rubber 21.49 J° /cm —PLA/rubber blends should form immiscible blends, which was confirmed by the presence of two Tg s in the blends. To investigate the effects of matrix crystallinity on impact and tensile strengths, PL As composed of different LLA/DLA ratios (PLLA, PDLLA (95/5), and PDLLA (50/ 50)) were blended with poly( -CL/L-lac) rubbers (0-30 wt %). Poly( -CL/L-lac) rubber had a Tg around —28°C and the relatively long sequence of LLA segments was capable of crystallization. Incorporation of poly( -CL/L-lac) rubber... 

From the Eqs. (11) and (12) it follows, that a common variation x =0-0.72 is realized at the constant value A=0.72, that is, this parameter does not depend on crystallinity degree and it is defined only by polymer matrix crystalline morphology... 

Based on the DSC curves, there were similar characteristics found for both unfilled CAB and whiskers-filled CAB. Figure 13.4 shows the first-heating DSC curves for the composites between 120 and 180°C. Moreover, the melting temperatures, heats of fusion and estimated crystallinity can be seen in Table 13.4. As the percentage of reinforcement increases, both matrix crystallinity and heat of fusion slightly decrease, while melting temperatures remain steady and constant. The addition of kenaf whiskers into the matrix did not seem to have any effect on CAB recrystallization. 

As the percentage of reinforcement increases, both matrix crystallinity and heat of fusion slightly decrease, while melting temperatures remain steady and constant. The addition of kenaf whiskers into the matrix did not seem to have any effect on CAB recrystallization. 

These impact properties depend on the EPR rubber dispersion, composition, and particle sizes and on the matrix crystallinity. However, such modifications to improve the impact properties are often detrimental to other desired properties such as high stiffness and HDT. The development of these new systems shows an improved balance between properties and therefore represents one of the major challenges within the PP industry. Eor instance, an improved balance between impact strength and stiffness, impact strength and transparency as well as impact strength... 

Crystallization nuclei Increase Increase matrix crystallinity Because the fiber surface acts as a crystallization nuclei... 

Mechanical properties of WPCs also undergo changes after weathering, which can be attributed to composite surface oxidation, matrix crystallinity changes, and interfacial degradation. 

Kaur J, Lee JH, Shofner ML. Influence of polymer matrix crystallinity on nanocomposite morphology and properties. Polymer 2011 52 4337 44. 

Similarly, to reveal the origin of the interfacial filaments between PLA and PBS nanofibrils, the matrix crystalline morphology is tracked by etching the amorphous PLA component as manifested in Fig. 8.9, where PBS nanofibrils are wrapped by regularly aligned lamellae perpendicular to the nanofibril axis, serving as the central... 

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