Despite the commercial importance of maleic anhydride grafted polypropylene (PP-g-MAH), it has long been a scientific challenge to prepare this polymer with a wellcontrolled molecular structure. This paper discusses a new chemical route that can form PP-g-MAH with desirable MAH content, a single MAH incorporated unit, white color, high molecular weight, and narrow molecular weight and composition distributions. The chemistry involves a unique PP-co-p-BT copolymer as the "reactive intermediate" that can be effectively prepared by metallocene-mediated copolymerization of propylene and p-(3-butenyl)toluene (p-BT), with narrow molecular weight and composition distributions, high molecular weight, and a broad range of p-BT contents. The incorporated p-BT comonomer units provide the reactive sites for the subsequent free radical MAH graft reaction under a suspension condition at a low reaction temperature. The resulting PP-g-MAH polymers were carefully examined by a combination of NMR and GPC measurements, which shows almost no change in polymer molecular weight and distribution and a single MAH incorporation (no oligomerization). The incorporated MAH units increase with the increase of initiator concentration, p-BT content, and reaction time. Evidently, the combination of high reactivity of φ-CH 3 moiety, a favorable mixing condition between the reactive sites and chemical reagents in the swollen amorphous phases, and low reaction temperature results in MAH grafting reaction selectively taking place at the φ-CH 3 moieties without side reactions (i.e., chain degradation and MAH oligomerization). In addition, this suspension reaction process presents an economic method to prepare PP-g-MAH with high polymer content and easy product purification.

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Development of a bio-based wood adhesive is a significant goal for several wood-based material industries. In this study, a novel adhesive based upon sucrose and ammonium dihydrogen phosphate (ADP) was formulated in hopes of furthering this industrial goal through realization of a sustainable adhesive with mechanical properties and water resistance comparable to the synthetic resins used today. Finished particleboards exhibited excellent mechanical properties and water resistance at the revealed optimal adhesive conditions. In fact, the board properties fulfilled in principle the requirements of JIS A 5908 18 type standard, however this occured at production conditions for the actual state of development as reported here, which are still different to usual industrial conditions. Thermal analysis revealed addition of ADP resulted in decreases to the thermal thresholds associated with degradation and curing of sucrose. Spectral results of FT-IR elucidated that furanic ring chemistry was involved during adhesive curing. A possible polycondensation reaction pathway was proposed from this data in an attempt to explain why the adhesive exhibited such favorable bonding properties.

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