The structural features of four different kraft papers were related to their surface properties and to the response upon industrial impregnation with phenol-formaldehyde (PF) resin. The chemical composition and the structure of paper were suggested to be important factors determining the interaction with PF resin, which was assessed by contact angle measurements and surface energy analysis. The presence of fatty matter (extractives) and inorganic fillers together with structural anisotropy of paper confers the difference in affinity of the face and backside of papers toward PF resin. This affects the resin distribution in impregnated precured kraft papers as revealed by microfluorescence spectroscopic analysis of transversal cuts.

Bleached acid sulphite and kraft Eucalyptus globulus pulps were subjected to treatment at high hydrostatic pressure (400 MPa during 10 min). The associated structural changes of cellulose were evaluated by X-ray scattering, solid-state NMR and infrared spectroscopy. The high pressure treatment promoted the growth of crystalline domains predominantly via lateral aggregation (cocrystallization) and, to some extent, due to the accretion of cellulose from noncrystalline domains (recrystallization). The treated pulps exhibited increment of the amount of strongly bound water and improved accessibility to amorphous domains. The high pressure treatment of dried sulphite pulp led to restoration, at least partially, of its swelling capacity thus diminishing the hornification features. Pressure treated dried sulphite pulp showed improved fibre bonding capacity at simultaneously increased bulk of the produced handsheets. The results obtained clearly showed the potential of high pressure treatments for the modification of cellulosic fibres in different applications.

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A crucial problem for laminate producers is the dimensional instability of decorative papers during soaking in aqueous solutions, but the source of this dilemma is not completely understood yet. In this study, eight commercial decorative papers of similar fiber composition and sizing were analyzed for their structural, physical, and mechanical properties. These properties were examined for their correlations to the dimensional stability of papers when moistened, as assessed by the wet stretch dynamics. Structure-to-property relationships were evaluated by principal component analysis (PCA). Within the set of parameters examined, PCA revealed that fiber orientation and the content of fillers/pigments influenced the wet expansion of paper web and affected its margins and dimensions in longitudinal and transverse directions of the paper machine. These variables are discussed within the context of decorative paper engineering in order to produce high performance papers with regular wet expansion properties.

The effect of high pressure (HP) pre-treatments on the subsequent enzymatic hydrolysis of cellulose from bleached kraft Eucalyptus globulus pulp by cellulase from Tricoderma viride was evaluated. Pressure pre-treatments of 300 and 400 MPa during 5-45 min, lead to both an increased rate and degree of hydrolysis, reaching values ranging from 1.5-to 1.9-fold, quantified by the formation of reducing sugars. Both the pressure and time under pressure influenced the enzymatic hydrosability of the cellulosic pulps, with the former being more important. The results indicate that the pressure pre-treatments promoted an increased accessibility of cellulose towards cellulase in the cell wall. The results obtained open promising possibilities, to contribute to overcome conventional limitations of enzymatic cellulose hydrolysis for the production of fermentable glucose, for the production of second generation bioethanol and chemicals by enhancement of both rate and yield of hydrolysis. The results are also of interest for the preparation of "pressure engineered" celullose with incremented tailored hydrolysis patterns.