Раздаточные материалы готовы на случай если сборников тезисов не хватит.

Раздаточные материалы is a common phrase meaning handouts, printed materials for distribution, or more generally materials to be given out.

It is plural:

• раздаточные = plural adjective, for handing out / distributive
• материалы = plural noun, materials

The singular would be раздаточный материал, but in practice the plural is very common when talking about sets of handouts.

Готовы is the short-form plural adjective of готовый (ready).

It agrees with раздаточные материалы, which is plural:

• материал готов = the material is ready
• материалы готовы = the materials are ready

Russian often uses short-form adjectives like this to express a state:

• Документы готовы. = The documents are ready.
• Обед готов. = Lunch is ready.

So раздаточные материалы готовы means the handouts are ready / prepared.

It means in case.

It introduces a possible situation that someone is preparing for:

• на случай, если пойдёт дождь = in case it rains
• на случай, если он опоздает = in case he is late

In your sentence, it means the handouts are ready in case the other materials are not enough.

Usually, yes: learners are safest writing на случай, если.

So the more standard punctuation would be:

Раздаточные материалы готовы на случай, если сборников тезисов не хватит.

You may sometimes see на случай если without a comma, because speakers/writers can treat it as a more fixed unit. But for careful written Russian, на случай, если is the safest choice.

Because the sentence is about a possible future situation.

• не хватает = is not enough / are not enough right now
• не хватит = will not be enough

Here the speaker means something like: the handouts are ready in case later there turn out not to be enough abstract booklets.

Also, хватит is from the perfective verb хватить, which commonly gives this simple future meaning:

• бумаг не хватит = there will not be enough paper
• времени хватит = there will be enough time

Because with хватать / хватить in the sense of to be enough / not enough, Russian often puts the thing that is sufficient or insufficient in the genitive.

Compare:

• денег хватит = there will be enough money
• времени не хватает = there isn’t enough time
• книг не хватит = there won’t be enough books

So:

• сборники = nominative plural
• сборников = genitive plural

The sentence uses the genitive because it means there may not be enough of the abstract booklets.

Because this is an impersonal-style quantity construction.

With хватит / не хватит, Russian often does not treat the noun as a normal nominative subject. Instead, the noun appears in the genitive, and the verb stays in 3rd person singular:

• книг не хватит
• денег хватит
• людей не хватает

So even though English might think in terms of a plural subject, Russian is really expressing “there will not be enough of X.”

Because this is really a noun phrase inside a noun phrase.

Base phrase:

• сборник тезисов = a collection/booklet of abstracts

Here:

• сборник is the main noun
• тезисов depends on it and means of abstracts / of theses

Then the whole phrase has to go into the genitive after не хватит:

• nominative singular: сборник тезисов
• genitive plural: сборников тезисов

So:

• сборников = genitive plural of сборник
• тезисов stays genitive plural because it already depends on сборник

Not necessarily in the English academic sense.

In Russian academic/event language, тезисы often means abstracts, summary points, or conference theses/abstract summaries, not a full dissertation or thesis.

So сборник тезисов is often best translated as:

• book of abstracts
• abstract booklet
• collection of conference abstracts

A native English speaker may be misled by the similarity between тезисы and theses, but in this context abstracts is often the more natural translation.

Yes. Russian word order is flexible.

The original sentence:

• Раздаточные материалы готовы на случай, если сборников тезисов не хватит.

This puts the main focus first: the handouts are ready.

You could also say:

• На случай, если сборников тезисов не хватит, раздаточные материалы готовы.

That version foregrounds the in case part first.

Both are grammatical. The difference is mainly one of emphasis and flow, not basic meaning.