I know it seems self evident that interesting material would be more persuasive, but someone went out an proved that point:

P. Karen Murphy and Patricia A. Alexander, “Persuasion as a Dynamic, Multidimensional Process: an Investigation of Individual and Intraindividual Differences,” American Educational Research Journal 41, no. 2 (Summer 2004): 337-63.

Definition of Persausion:

We speak of persuasion as an interactive process through which a given message alters an individual’s perspective by changing the knowledge, beliefs, or interest that underlie that perspective (Miller, 1980). Further a persuasive text is any message “structured to counter the current beliefs of a typical reader as well as to present new ones” by capitalizing on a reader’s existing knowledge and beliefs (Chambliss & Garner, 1996, p. 294). By defining persuasion and a persuasive text in this manner, we avoid casting this critical process in “all or nothing” terms (e.g., Hovland, Janis & Kelley, 1953). That is, we allow for incremental change that does not necessarily result in a radical or complete transformation in understanding or attitude. We also understand persuasion to be a mechanism for encouraging individuals to examine a concept or subject more closely or rom a different perspective. Such a process involves examining evidence that supports or refutes claims and critically weighing arguments (Toulmin, 1958). So defined, persuasion is neither inherently good nor evil, but a catalyst for thinking analytically about messages encountered by individuals (Alexander, Fives, Buehl & Mulhern, 2002; Hynd, 2001).

p. 338

Key elements:

Petty and Cacioppo (19860, among the most influential persuasion researchers, portray the interplay of credibility, emotions, and arguments as the keys to change.

p. 339

Peripheral and Central Route Processing:

According to Petty and Cacioppo’s (1986) Elaboration Likelihood Model, individuals process persuasive messages through two distinct routes: peripheral and central. Individuals who do not attend reflectively or critically to the persuasive arguments presented, but are captivated by the emotions of the situation or the character of the speaker, ravel the peripheral route. In contrast, individuals who weigh the argument thoughtfully and logically, are personally motivated, and cognitively able to attend to the message follow the central route. Although attitudinal change is expected from both paths, those who travel the central route are apt to experience deeper and more permanent effects than those who follow the more peripheral path to persuasion.

p. 339

A more able reader is more likely to be persuaded:

Moreover, it has been determined that individual’s ability to process a given message increases the likelihood that the message will prove persuasive. Consequently, those with greater comprehension skills are more apt to process the content of a persuasive message at a deeper level than those who comprehension skills are marginal or weak (Dole & Sinatra, 1998). Similarly, there is evidence that individuals who are more capable of retrieving relevant beliefs, whether in concert or in opposition to the author, are more likely to process the arguments presented, consequently are more likely to be persuaded (Wood & Kallgren, 1998).

p. 339.
Interesting material is more likely to persuade:

When readers are unable to grasp the meaning or perceive its relevance, they are unlikely to be persuaded.

p. 340

As mentioned previously, features of texts such as their interestingness, comprehensibility, and credibility have been shown to play a significant role in the persuasion process (e.g., Allen, 1991; Dole & Sinatra, 1998).

p. 341

We found that compelling articles, presented to readers in an unmodified state, performed well as catalysts for persuasion. As a result of reading these persuasive magazine articles, participants’ knowledge and interests grew and their beliefs became more like the beliefs advocated by the authors in the texts.

p. 359

Where the reader already has substantial knowledge, he is harder to persuade:

Second, we found that there was an inverse relationship between what individuals believe they know about a topic and the degree of agreement with the author they report after reading. In effect, it may be that too much topic-specific knowledge can be an impediment to change in beliefs.

p. 357