Fibres pulping/fibrillation

Higher magnification of the washed composite fillers shows that filler is precipitated in the pits and surface of the pulp fibres (Fig. 5.10). Significant proportion of filler is agglomerated and patches of filler are observed on the surface of the fibres and fibrils with Supermass colloider refined samples. Valley beater shows reduced agglomeration and retention of filler in the washed samples. Also, a minor fraction of calcium carbonate is precipitated inside the pits of fibres. 

Nanofibrillated fibres may also be used to make nonwovens using the wetlaid process. Fibrillation is the process of splitting fibres into fibrils or thin filaments, and is commonly conducted using wet mechanical beating to partially separate fibres into their component fibrils [16]. Nanofibrous cellulose has been produced from lyocell, cotton, and wood pulp, although the fibre diameter variation is high [17]. Fibril diameters between 0.05 and 0.5 pm have been observed, with an average of 0.3 pm, but a small number of microscale fibres (2—5 pm) are inevitable. 

The combined effect of high modulus polyethylene fibre which can be considered as the reinforcing fibre and fibrillated polypropylene pulp, which is effective for processing, was reported by Souroshian etal. [107] showing positive interactions between the two with respect to hardened composite properties. 

The fibres of CTMP pulps are more supple, less prone to fibrillation and fines production, and are more easily bonded than corresponding TMP fibres produced at the same level of energy input, and... 

Mechanical pulp mills are normally on the same site and integrated with paper production, e.g. of newsprint. Chemical pulp mills can be integrated or sell market pulp that is flash dried and baled. Here, the capillary tension on drying pulls baek the loose fibrillated wall elements to re-bond to the external surface of the fibre, and... 

Synthetic wood-pulp separators (SWP). So-called synthetic wood-pulp (SWP) separators are used widely in Japan for automotive batteries. These are fleeces made from fibrillated polyethylene or polypropylene and small amounts of additional fibres (e.g., polyester fibres) sometimes, the fleeces are also filled with silica. The organic sheets are laminated with a glass mat, which serves to stabilize the positive active-material [39]. 

Iwamoto S, Nakagaito AN, Yano H (2007) Nano-fibrillation of pulp fibres for the processing of transparent nanocomposites. Appl Phys A-Mater Sci Process 89 461-466 Klemm D, Schumann D, Kramer F, Hessler N, Homung M, Schmauder HP, Marsch S et al (2006) Nanocelluloses as innovative polymers in research and application. Polysaccharides 205 49-96... 

This chapter aims to introduce the concept of nanocellulosic-fibril and precipitated calcium carbonate (PCC) composites. The effect of cogrinding of lime and pulp fibres and different precipitation conditions on the production of PCC and modification of its morphologies are analysed in this chapter. 

Laboratory Hollander refining - a Hollander beater design consists of a circular or ovoid water raceway with a beater wheel at a single point along the raceway. The beater wheel is made with multiple blades mounted on an axle-Uke shaft, similar to the construction of a water wheel. Under power, the blades rotate to beat the fibre into usable pulp slurry or highly fibrillated pulp suspension composed of ceUulosic fibrils and fibres. In our study, we used a valley beater, and, hence, in this study the words Hollander and valley beater are used interchangeably. Co-refining of pulp fibre and lime was carried out to a maximum of 30 min in the Hollander beater. 

Nakagaito AN, Yano H (2004) The effect of morphological changes from pulp fibre towards nanoscale fibrillated cellulose on the mechanical properties of high-strength plant fibre based composites. Appl Phys A 78 547-552... 

In the human spleen, vinyl chloride-induced lesions were primarily but not a consequence of portal hypertension (Heusermann and Stutte 1977, Stutte and Heusermann 1977). Fibre-associated reticulum cells of the red pulp and fibroblastic reticulum cells in white pulp were stimulated to produce excessive amounts of the extracellular elements of connective tissue, especially collagen fibrils. 

An interesting development for thermoplastics is a technique for pulping or fibrillation that greatly increases the surface area of short-length fibres of para-aramid, and renders them suitable for reinforcement of plastics and elastomers. While a typical staple fibre will have a surface area of about 0.1 m g K the new compounding process increases this to 7-9 g, so increasing the area... 

The specimens of soil with fibres and cement or cactus pulp as a binder were subjected to bending, abrasion, erosion and water absorption. Sisal fibres 40-50 mm long and polypropylene fibrillated fibres 20 mm long were... 

Polyethylene fibres have been evaluated using either short, dispersed fibres mixed with concrete at volumes up to about 4% [84], or a continuous network of fibrillated fibres (polyethylene in pulp form) to produce a composite with about 10% by volume of fibres. In pulp form, they are intended for use as asbestos replacement. The effect of short, discontinuous fibres (load-deflection of concrete is shown in Figure 10.20. At a volume content of 2% the fibres led to a marked post-cracking load-bearing capacity, while at 4% the maximum load in the post-cracking range exceeded the first crack stress. Thus, these fibres seem to be very effective for crack control. The fibrillated continuous polyethylene fibres appeared to be more effective than similar polypropylene fibres, probably because of the higher elastic modulus of the polyethylene. 

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