Abstract: A method for isomerizing methyltetrahydrophthalic anhydride includes the following processes. A liquid reactant is provided. Under a condition of injecting nitrogen gas, an alkaline catalyst is added into the liquid reactant for an isomerization reaction, so as to obtain an isomerization product. The liquid reactant includes 3-methyltetrahydrophthalic anhydride and 4-methyltetrahydrophthalic anhydride. Based on a total weight of the isomerization product being 100 wt %, an amount of a methyltetrahydrophthalic anhydride dimer is lower than 1.6 wt %.

Abstract: A method for manufacturing methyltetrahydrophthalic anhydride is provided, which includes steps as follows. Maleic anhydride is added into a reactor. Piperylene is added into the reactor, so that the piperylene and the maleic anhydride undergo a first addition reaction. When a conversion rate of the maleic anhydride is more than 25%, the first addition reaction is completed. Isoprene is added into the reactor, so that the isoprene and the maleic anhydride undergo a second addition reaction to obtain a methyltetrahydrophthalic anhydride product. The methyltetrahydrophthalic anhydride product contains 3-methyltetrahydrophthalic anhydride and 4-methyltetrahydrophthalic anhydride.

Abstract: A method for manufacturing methyltetrahydrophthalic anhydride is provided, which includes steps as follows. Maleic anhydride is added into a reactor. Piperylene is added into the reactor, so that the piperylene and the maleic anhydride undergo a first addition reaction. When a conversion rate of the maleic anhydride is more than 25%, the first addition reaction is completed. Isoprene is added into the reactor, so that the isoprene and the maleic anhydride undergo a second addition reaction to obtain a methyltetrahydrophthalic anhydride product. The methyltetrahydrophthalic anhydride product contains 3-methyltetrahydrophthalic anhydride and 4-methyltetrahydrophthalic anhydride.

Abstract: A method for manufacturing a low-viscosity hardener is provided. The method includes the followings steps: providing a hardener crude product; and subjecting the hardener crude product and an alkaline catalyst to an isomerization reaction, so as to obtain the low-viscosity hardener. The hardener crude product contains 3-methyltetrahydrophthalic anhydride and 4-methyltetrahydrophthalic anhydride, and a weight ratio of the 3-methyltetrahydrophthalic anhydride to the 4-methyltetrahydrophthalic anhydride ranges from 7:3 to 3:7. A viscosity of the low-viscosity hardener ranges from 30 cps to 50 cps.

Abstract: A plasticizer and a method for manufacturing the plasticizer are provided. The method for manufacturing the plasticizer includes steps as follows: mixing a dicarboxylic acid, a diol, and a catalyst to form a reactant mixture; reacting the reactant mixture at a temperature ranging from 130° C. to 220° C. so as to form a semi-product; adding an endcapping alcohol into the semi-product at a temperature ranging from 205° C. to 220° C. so as to form a coarse plasticizer; purifying the coarse plasticizer under a pressure ranging from 760 Torr to 5 Torr so as to obtain the plasticizer. The dicarboxylic acid includes adipic acid. The diol includes a polyglycol and a saturated fatty alcohol. The endcapping alcohol includes isooctyl alcohol, isodecyl alcohol, or 2-propylheptanol. The dicarboxylic acid, the diol, and the endcapping alcohol have a molar ratio ranging from 1:0.6 to 0.9:0.3 to 0.6.

Abstract: A plasticizer and a method for manufacturing the plasticizer are provided. The method includes the following steps. A dicarboxylic acid, a diol, and a catalyst are mixed to form a reactant mixture. The reactant mixture is reacted at a temperature ranging from 130° C. to 220° C. to form a semi-product. An endcapping alcohol is added into the semi-product at a temperature ranging from 205° C. to 220° C. to form a coarse plasticizer. The coarse plasticizer is purified under a pressure ranging from 760 Torr to 5 Torr to obtain the plasticizer. The dicarboxylic acid includes succinic acid or adipic acid. The diol includes diethylene glycol and 2-methyl-1,3-propanediol. The endcapping alcohol is an ether alcohol or a fatty alcohol having a carbon number of less than or equal to 4. The dicarboxylic acid, the diol, and the endcapping alcohol have a molar ratio ranging from 1:0.6 to 0.9:0.3 to 0.6.

Abstract: A plasticizer and a method for manufacturing the plasticizer are provided. The method includes steps as follow. A dicarboxylic acid, a diol, and a catalyst are mixed to form a reactant mixture. The reactant mixture is reacted at a temperature ranging from 130° C. to 220° C. to form a semi-product. An endcapping alcohol into the semi-product at a temperature ranging from 205° C. to 220° C. to form a coarse plasticizer. The coarse plasticizer is purified under a pressure ranging from 760 Torr to 5 Torr to obtain the plasticizer. The dicarboxylic acid includes a first dicarboxylic acid and a second dicarboxylic acid, and the second dicarboxylic acid is adipic acid. The diol includes diethylene glycol and 2-methyl-1, 3-propanediol. The endcapping alcohol includes isooctyl alcohol, isodecyl alcohol, or 2-propylheptanol. A molar ratio of dicarboxylic acid:diol:the endcapping alcohol ranges from 1:0.6 to 0.9:0.3 to 0.6.

Abstract: A method for manufacturing nonylcyclohexanol is provided. The method includes steps as follows: adding a liquid phase reactant into a reactor, and the liquid phase reactant includes a molten nonylphenol and a catalyst; introducing a gas phase reactant to maintain a pressure of the gas phase reactant to be from 36.5 bar to 70 bar, and the gas phase reactant consists of hydrogen; rotating a hollow stirring shaft of the reactor at a temperature of from 100° C. to 130° C. so that the gas phase reactant is transported through a channel formed in the hollow stirring shaft into the liquid phase reactant for carrying out a reaction; obtaining a product that contains nonylcyclohexanol. A conversion rate of the nonylcyclohexanol is higher than or equal to 99.0%.

Abstract: A polyphenylene ether resin modified with two amino functional groups, a method for producing the same, and a substrate material for a circuit board are provided. The polyphenylene ether resin modified with the two amino functional groups has a structural formula as follows: in which R represents a chemical group that is located between two hydroxyphenyl functional groups of a bisphenol compound, and n is an integer between 3 and 25, inclusive.